Heterocyclic compound and organic light-emitting device including the same

ABSTRACT

Provided are a heterocyclic compound and an organic light-emitting device including the same. The heterocyclic compound is represented by Formula 1:

CROSS-REFERENCE TO RELATED APPLICATION

Korean Patent Application No. 10-2017-0002556, filed on Jan. 6, 2017, inthe Korean Intellectual Property Office, and entitled: “HeterocyclicCompound and Organic Light-Emitting Device Including the Same,” isincorporated by reference herein in its entirety.

BACKGROUND 1. Field

Embodiments relate to a heterocyclic compound and an organiclight-emitting device including the same.

2. Description of the Related Art

Organic light-emitting devices are self-emission devices and producefull-color images, and also have wide viewing angles, high contrastratios, short response times, as well as excellent characteristics interms of brightness, driving voltage, and response speed.

An example of such organic light-emitting devices may include a firstelectrode disposed on a substrate, and a hole transport region, anemission layer, an electron transport region, and a second electrode,which are sequentially disposed on the first electrode. Holes providedfrom the first electrode may move toward the emission layer through thehole transport region, and electrons provided from the second electrodemay move toward the emission layer through the electron transportregion. Carriers, such as holes and electrons, may recombine in theemission layer to produce excitons. Excitons transiting from an excitedstate to a ground state may generate light.

SUMMARY

Embodiments are directed to a heterocyclic compound represented byFormula 1:

In Formula 1,

A₁ and A₂ are each independently selected from a C₅-C₆₀ carbocyclicgroup or a C₂-C₆₀ heterocyclic group,

X and Y are each independently oxygen (O) or sulfur (S),

L₁ and L₂ are each independently selected from a substituted orunsubstituted C₅-C₆₀ carbocyclic group or a substituted or unsubstitutedC₁-C₆₀ heterocyclic group, *—Si(Q₁)(Q₂)-*′, *—N(Q₁)-*′, *—B(Q₁)-*′,*—C(═O)—*′, *—S(═O)₂+*′, and *—P(═O)(Q₁)-*′,

a1 and a2 are each independently an integer selected from 0 to 5,

when a1 is equal to 0, *-(L₁)_(a1)-*′ is a single bond, and when a2 isequal to 0, *-(L₂)_(a2)-*′ is a single bond,

Ar₁ and Ar₂ are each independently selected from a substituted orunsubstituted C₃-C₁₀ cycloalkyl group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀cycloalkenyl group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀ arylgroup, a substituted or unsubstituted C₆-C₆₀ aryloxy group, asubstituted or unsubstituted C₆-C₆₀ arylthio group, a substituted orunsubstituted monovalent non-aromatic condensed polycyclic group, asubstituted or unsubstituted monovalent non-aromatic condensedheteropolycyclic group, —Si(Q₁)(Q₂)(Q₃), —N(Q₁)(Q₂), —B(Q₁)(Q₂),—C(═O)(Q₁), —S(═O)₂(Q₁), and —P(═O)(Q)(Q₂),

b1 and b2 are each independently an integer selected from 1 to 5,

R₁ and R₂ are each independently selected from hydrogen, deuterium, —F,—Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidinogroup, a hydrazino group, a hydrazono group, a substituted orunsubstituted C₁-C₆₀ alkyl group, a substituted or unsubstituted C₂-C₆₀alkenyl group, a substituted or unsubstituted C₂-C₆₀ alkynyl group, asubstituted or unsubstituted C₁-C₆₀ alkoxy group, a substituted orunsubstituted C₃-C₁₀ cycloalkyl group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀cycloalkenyl group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀ arylgroup, a substituted or unsubstituted C₆-C₆₀ aryloxy group, asubstituted or unsubstituted C₆-C₆₀ arylthio group, a substituted orunsubstituted C₁-C₆₀ heteroaryl group, a substituted or unsubstitutedmonovalent non-aromatic condensed polycyclic group, a substituted orunsubstituted monovalent non-aromatic condensed heteropolycyclic group,—Si(Q₁)(Q₂)(Q₃), —C(═O)(Q₁), —S(═O)₂(Q₁), and —P(═O)(Q₁)(Q₂),

c1 and c2 are each independently an integer selected from 0 to 7,

m and n are each independently an integer selected from 0 to 8, and thesum of m and n is equal to or greater than 1,

at least one substituent selected from the substituted C₃-C₆₀carbocyclic group, the substituted C₂-C₆₀ heterocyclic group, thesubstituted C₁-C₆₀ alkyl group, the substituted C₂-C₆₀ alkenyl group,the substituted C₂-C₆₀ alkynyl group, the substituted C₁-C₆₀ alkoxygroup, the substituted C₃-C₁₀ cycloalkyl group, the substituted C₁-C₁₀heterocycloalkyl group, the substituted C₃-C₁₀ cycloalkenyl group, thesubstituted C₁-C₁₀ heterocycloalkenyl group, the substituted C₆-C₆₀ arylgroup, the substituted C₆-C₆₀ aryloxy group, the substituted C₆-C₆₀arylthio group, the substituted C₁-C₆₀ heteroaryl group, the substitutedmonovalent non-aromatic condensed polycyclic group, and the substitutedmonovalent non-aromatic condensed heteropolycyclic group is selectedfrom:

deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, asubstituted or unsubstituted C₁-C₆₀ alkyl group, a substituted orunsubstituted C₂-C₆₀ alkenyl group, a substituted or unsubstitutedC₂-C₆₀ alkynyl group, and a substituted or unsubstituted C₁-C₆₀ alkoxygroup;

a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group,and a C₁-C₆₀ alkoxy group, each substituted with at least one selectedfrom deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, anitro group, an amidino group, a hydrazino group, a hydrazono group, aC₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,a monovalent non-aromatic condensed heteropolycyclic group,—Si(Q₁)(Q₁₂)(Q₁₃), —N(Q₁₁)(Q₁₂), —B(Q₁)(Q₁₂), —C(═O)(Q₁₁), —S(═O)₂(Q₁₁),and —P(═O)(Q₁₁)(Q₁₂);

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group;

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenylgroup, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, amonovalent non-aromatic condensed polycyclic group, a monovalentnon-aromatic condensed heteropolycyclic group, —Si(Q₂₁)(Q₂₂)(Q₂₃),—N(Q₂₁)(Q₂₂), —B(Q₂₁)(Q₂₂), —C(═O)(Q₂₁), —S(═O)₂(Q₂₁), and—P(═O)(Q₂₁)(Q₂₂); and

—Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁),—S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), and

Q₁ to Q₃, Q₁₁ to Q₁₃, Q₂₁ to Q₂₃, and Q₃₁ to Q₃₃ are each independentlyselected from hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, acyano group, a nitro group, an amidino group, a hydrazino group, ahydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, aC₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₁-C₆₀ heteroarylgroup, a monovalent non-aromatic condensed polycyclic group, amonovalent non-aromatic condensed heteropolycyclic group, a biphenylgroup, and a terphenyl group.

Embodiments are also directed to an organic light-emitting deviceincluding: a first electrode; a second electrode facing the firstelectrode; and an organic layer disposed between the first electrode andthe second electrode and including an emission layer, wherein theorganic layer includes a heterocyclic compound according to anembodiment.

BRIEF DESCRIPTION OF THE DRAWINGS

Features will become apparent to those of skill in the art by describingin detail exemplary embodiments with reference to the attached drawingsin which:

FIGS. 1 to 4 each illustrate a schematic view of an organiclight-emitting device according to an embodiment.

DETAILED DESCRIPTION

Example embodiments will now be described more fully hereinafter withreference to the accompanying drawings; however, they may be embodied indifferent forms and should not be construed as limited to theembodiments set forth herein. Rather, these embodiments are provided sothat this disclosure will be thorough and complete, and will fullyconvey exemplary implementations to those skilled in the art. Likereference numerals refer to like elements throughout.

As used herein, the term “and/or” includes any and all combinations ofone or more of the associated listed items. Expressions such as “atleast one of,” when preceding a list of elements, modify the entire listof elements and do not modify the individual elements of the list.

According to an aspect of embodiments, a heterocyclic compound isrepresented by Formula 1:

In Formula 1, A₁ and A₂ may each independently be a C₅-C₆₀ carbocyclicgroup or a C₂-C₆₀ heterocyclic group.

In an embodiment, A₁ and A₂ in Formula 1 may each independently beselected from a benzene group, a naphthalene group, an anthracene group,and a phenanthrene group.

For example, A₁ and A₂ in Formula 1 may each independently be a benzenegroup and a naphthalene group.

In Formula 1, X and Y may each independently be oxygen (O) or sulfur(S).

In an embodiment, X and Y in Formula 1 may be identical to or differentfrom each other. For example, in Formula 1, X may be O and Y may be S; Xmay be S and Y may be O; or both X and Y may be O or S.

In Formula 1, L₁ and L₂ may each independently be a substituted orunsubstituted C₅-C₆₀ carbocyclic group or a substituted or unsubstitutedC₁-C₆₀ heterocyclic group, *—Si(Q₁)(Q₂)-*′, *—N(Q₁)-*′, *—B(Q₁)-*′,*—C(═O)⁻*′, *—S(═O)₂—*′, and *—P(═O)(Q₁)-*′.

In one or more embodiments, L₁ and L₂ in Formula 1 may eachindependently be a divalent group based on a group selected from:

a benzene group, a pentalene group, an indene group, a naphthalenegroup, an azulene group, an indacene group, an acenaphthalene group, afluorene group, a spiro-bifluorene group, a benzofluorene group, adibenzofluorene group, a phenalene group, a phenanthrene group, ananthracene group, a fluoranthene group, a triphenylene group, a pyrenegroup, a chrysene group, a perylene group, a pentacene group, a pyrrolegroup, a thiophene group, a furan group, a silole group, an imidazolegroup, a pyrazole group, a thiazole group, an isothiazole group, anoxazole group, an isoxazole group, a pyridine group, a pyrazine group, apyrimidine group, a pyridazine group, an indole group, an iso-indolegroup, an indazole group, a purine group, a quinoline group, anisoquinoline group, a benzoquinoline group, a benzoisoquinoline group, aphthalazine group, a naphthyridine group, a quinoxaline group, aquinazoline group, a cinnoline group, a phenanthridine group, anacridine group, a phenanthroline group, a phenazine group, abenzimidazole group, a benzofuran group, a benzothiophene group, abenzosilole group, a benzothiazole group, an iso-benzothiazole group, abenzoxazole group, an isobenzoxazole group, a triazole group, atetrazole group, an oxadiazole group, a triazine group, a carbazolegroup, a dibenzofuran group, a dibenzothiophene group, a dibenzosilolegroup, a benzocarbazole group, a naphtho benzofuran group, a naphthobenzothiophene group, a naphthobenzosilole group, a dibenzocarbazolegroup, a dinaphthofuran group, a dinaphthothiophene group, adinaphthosilole group, a thiadiazol group, an imidazopyridine group, animidazopyrimidine group, an oxazolpyridine group, a thiazolpyridinegroup, a benzonaphthyridine group, an azafluorene group, anazaspiro-bifluorene group, an azacarbazole group, an azadibenzofurangroup, an azadibenzothiophene group, an azadibenzosilole group, anindeno pyrrole group, an indolopyrrole group, an indeno carbazole group,and an indolocarbazole group;

a benzene group, a pentalene group, an indene group, a naphthalenegroup, an azulene group, an indacene group, an acenaphthalene group, afluorene group, a spiro-bifluorene group, a benzofluorene group, adibenzofluorene group, a phenalene group, a phenanthrene group, ananthracene group, a fluoranthene group, a triphenylene group, a pyrenegroup, a chrysene group, a perylene group, a pentacene group, a pyrrolegroup, a thiophene group, a furan group, a silole group, an imidazolegroup, a pyrazole group, a thiazole group, an isothiazole group, anoxazole group, an isoxazole group, a pyridine group, a pyrazine group, apyrimidine group, a pyridazine group, an indole group, an iso-indolegroup, an indazole group, a purine group, a quinoline group, anisoquinoline group, a benzoquinoline group, a benzoisoquinoline group, aphthalazine group, a naphthyridine group, a quinoxaline group, aquinazoline group, a cinnoline group, a phenanthridine group, anacridine group, a phenanthroline group, a phenazine group, abenzimidazole group, a benzofuran group, a benzothiophene group, abenzosilole group, a benzothiazole group, an iso-benzothiazole group, abenzoxazole group, an isobenzoxazole group, a triazole group, atetrazole group, an oxadiazole group, a triazine group, a carbazolegroup, a dibenzofuran group, a dibenzothiophene group, a dibenzosilolegroup, a benzocarbazole group, a naphtho benzofuran group, a naphthobenzothiophene group, a naphthobenzosilole group, a dibenzocarbazolegroup, a dinaphthofuran group, a dinaphthothiophene group, adinaphthosilole group, a thiadiazol group, an imidazopyridine group, animidazopyrimidine group, an oxazolpyridine group, a thiazolpyridinegroup, a benzonaphthyridine group, an azafluorene group, anazaspiro-bifluorene group, an azacarbazole group, an azadibenzofurangroup, an azadibenzothiophene group, an azadibenzosilole group, anindeno pyrrole group, an indolopyrrole group, an indeno carbazole group,and an indolocarbazole group, each substituted with at least oneselected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amidino group, a hydrazino group, a hydrazonogroup, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a C₃-C₁₀ cycloalkylgroup, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, aC₁-C₁₀ heterocycloalkenyl group, a C₆-C₂₀ aryl group, a C₁-C₂₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,a monovalent non-aromatic condensed heteropolycyclic group, amethylphenyl group, a biphenyl group, and —Si(Q₃₁)(Q₃₂)(Q₃₃); and

*—P(═O)(Q₁)-*′, and

Q₁ and Q₃₁ to Q₃₃ may each independently be selected from:

a C₁-C₁₀ alkyl group, a C₁-C₁₀ alkoxy group, a phenyl group, a biphenylgroup, a terphenyl group, a naphthyl group, a pyridinyl group, apyrimidinyl group, a pyrazinyl group, a quinolinyl group, anisoquinolinyl group, a quinoxalinyl group, and a quinazolinyl group; and

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, apyridinyl group, a pyrimidinyl group, a pyrazinyl group, a quinolinylgroup, an isoquinolinyl group, a quinoxalinyl group, and a quinazolinylgroup, each substituted with at least one selected from a C₁-C₁₀ alkylgroup, a C₁-C₁₀ alkoxy group, and a phenyl group.

In one or more embodiments, in Formula 1, L₁ and L₂ may eachindependently be selected from groups represented by Formulae 3-1 to3-47:

In Formulae 3-1 to 3-47,

Y₁ may be O, S, C(Z₃)(Z₄), N(Z₅), or Si(Z₆)(Z₇),

Z₁ to Z₇ may each independently be selected from:

hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, an amidino group, a hydrazino group, a hydrazono group, aC₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a cyclopentyl group, acyclohexyl group, a cycloheptyl group, a cyclopentenyl group, acyclohexenyl group, a phenyl group, a biphenyl group, a terphenyl group,a pentalenyl group, an indenyl group, a naphthyl group, an azulenylgroup, an indacenyl group, an acenaphthyl group, a fluorenyl group, aspiro-bifluorenyl group, a spiro-benzofluorene-fluorenyl group, abenzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, aphenanthrenyl group, an anthracenyl group, a fluoranthenyl group, atriphenylenyl group, a pyrenyl group, a chrysenyl group, a perylenylgroup, a pentacenyl group, a pyrrolyl group, a thiophenyl group, afuranyl group, a silolyl group, an imidazolyl group, a pyrazolyl group,a thiazolyl group, an isothiazolyl group, an oxazolyl group, anisoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinylgroup, a pyridazinyl group, an indolyl group, an isoindolyl group, anindazolyl group, a purinyl group, a quinolinyl group, an isoquinolinylgroup, a benzoquinolinyl group, an isoquinolinyl group, a phthalazinylgroup, a naphthyridinyl group, a quinoxalinyl group, a benzoquinoxalinylgroup, a quinazolinyl group, a benzoquinazolinyl group, a cinnolinylgroup, a phenanthridinyl group, an acridinyl group, a phenanthrolinylgroup, a phenazinyl group, a benzimidazolyl group, a benzofuranyl group,a benzothiophenyl group, a benzosilolyl group, a benzothiazolyl group,an isobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolylgroup, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, atriazinyl group, a carbazolyl group, a dibenzofuranyl group, adibenzothiophenyl group, a dibenzosilolyl group, a benzocarbazolylgroup, a naphthobenzofuranyl group, a naphthobenzothiophenyl group, anaphthobenzosilolyl group, a dibenzocarbazolyl group, a dinaphthofuranylgroup, a dinaphthothiophenyl group, a dinaphthosilolyl group, athiadiazolyl group, an imidazopyridinyl group, an imidazopyrimnidinylgroup, an oxazolopyridinyl group, a thiazolopyridinyl group, abenzonaphthyridinyl group, an azafluorenyl group, anazaspiro-bifluorenyl group, an azacarbazolyl group, an azadibenzofuranylgroup, an azadibenzothiophenyl group, an azadibenzosilolyl group, anindenopyrrolyl group, an indolopyrrolyl group, an indeno carbazolylgroup, and an indolocarbazolyl group.

d2 may be an integer selected from 0 to 2,

d3 may be an integer selected from 0 to 3,

d4 may be an integer selected from 0 to 4,

d5 may be an integer selected from 0 to 5,

d6 may be an integer selected from 0 to 6,

d8 may be an integer selected from 0 to 8, and

* and *′ each indicate a binding site to a neighboring atom.

For example, in Formula 1, L₁ and L₂ may each independently be selectedfrom groups represented by Formulae 3-1, 3-2, 3-6, 3-8, 3-12, 3-24,3-32, and 3-47.

In Formula 1, a1 and a2 may each independently be an integer selectedfrom 0 to 5.

In an embodiment, in Formula 1, a1 and a2 may each independently be 0,1, or 2.

For example, when a1 is equal to 0, *-(L₁)_(a1)-*′ may be a single bond,and when a2 is equal to 0, *-(L₂)_(a2)-*′ may be a single bond. Forexample, when a1 is an integer of two or more, two or more L₁(s) may beidentical to or different from each other. For example, when a2 is aninteger of two or more, two or more L₂(s) may be identical to ordifferent from each other.

In Formula 1, Ar₁ and Ar₂ may each independently be selected from asubstituted or unsubstituted C₃-C₁₀ cycloalkyl group, a substituted orunsubstituted C₁-C₁₀ heterocycloalkyl group, a substituted orunsubstituted C₃-C₁₀ cycloalkenyl group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀aryl group, a substituted or unsubstituted C₆-C₆₀ aryloxy group, asubstituted or unsubstituted C₆-C₆₀ arylthio group, a substituted orunsubstituted monovalent non-aromatic condensed polycyclic group, asubstituted or unsubstituted monovalent non-aromatic condensedheteropolycyclic group, —Si(Q₁)(Q₂)(Q₃), —N(Q₁)(Q₂), —B(Q₁)(Q₂),—C(═O)(Q₁), —S(═O)₂(Q₁), and —P(═O)(Q₁)(Q₂).

In an embodiment, in Formula 1, A₁ and Ar₂ may each independently beselected from:

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a ifuranyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzolfuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, an imidazolyl group, apyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolylgroup, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group,a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinylgroup, a quinolinyl group, an isoquinolinyl group, a benzoquinolinylgroup, a phthalazinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a cinnolinyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolylgroup, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group,an imidazopyridinyl group, an imidazopyrimidinyl group, and anazacarbazolyl group; and

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, an imidazolyl group, apyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolylgroup, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group,a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinylgroup, a quinolinyl group, an isoquinolinyl group, a benzoquinolinylgroup, a phthalazinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a cinnolinyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolylgroup, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group,an imidazopyridinyl group, an imidazopyrimidinyl group, and anazacarbazolyl group, each substituted with at least one selected fromdeuterium. —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, a naphthyl group, a fluorenyl group, aspiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenylgroup, a phenanthrenyl group, an anthracenyl group, a fluoranthenylgroup, a triphenylenyl group, a pyrenyl group, a chrysenyl group, aperylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a thiophenyl group, a furanyl group, a carbazolyl group, anindolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, an imidazolyl group, apyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolylgroup, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group,a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinylgroup, a quinolinyl group, an isoquinolinyl group, a benzoquinolinylgroup, a phthalazinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a cinnolinyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolylgroup, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group,an imidazopyridinyl group, an imidazopyrimidinyl group, an azacarbazolylgroup, and —Si(Q₃₁)(Q₃₂)(Q₃₃); and

—Si(Q₁)(Q₂)(Q₃), —C(═O)(Q₁), —S(═O)₂(Q₁), and —P(═O)(Q₁)(Q₂), and

Q₁ to Q₃ and Q₃₁ to Q₃₃ may each independently be selected from:

a C₁-C₁₀ alkyl group, a C₁-C₁₀ alkoxy group, a phenyl group, a biphenylgroup, a terphenyl group, a naphthyl group, a pyridinyl group, apyrimidinyl group, a pyrazinyl group, a quinolinyl group, anisoquinolinyl group, a quinoxalinyl group, and a quinazolinyl group; and

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, apyridinyl group, a pyrimidinyl group, a pyrazinyl group, a quinolinylgroup, an isoquinolinyl group, a quinoxalinyl group, and a quinazolinylgroup, each substituted with at least one selected from a C₁-C₁₀ alkylgroup, a C₁-C₁₀ alkoxy group, and a phenyl group.

In one or more embodiments, in Formula 1, Ar₁ and Ar₂ may eachindependently be selected from groups represented by Formulae 5-1 to5-84:

In Formulae 5-1 to 5-84,

Y₃₁ may be O, S, C(Z₃₅)(Z₃₆), N(Z₃₇), or Si(Z₃₈)(Z₃₉),

Z₃₁ to Z₃₉ may each independently be selected from:

hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, an amidino group, a hydrazino group, a hydrazono group, aC₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a cyclopentyl group, acyclohexyl group, a cycloheptyl group, a cyclopentenyl group, acyclohexenyl group, a phenyl group, a biphenyl group, a terphenyl group,a pentalenyl group, an indenyl group, a naphthyl group, an azulenylgroup, an indacenyl group, an acenaphthyl group, a fluorenyl group, aspiro-bifluorenyl group, a spiro-benzofluorene-fluorenyl group, abenzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, aphenanthrenyl group, an anthracenyl group, a fluoranthenyl group, atriphenylenyl group, a pyrenyl group, a chrysenyl group, a perylenylgroup, a pentacenyl group, a pyrrolyl group, a thiophenyl group, afuranyl group, a silolyl group, an imidazolyl group, a pyrazolyl group,a thiazolyl group, an isothiazolyl group, an oxazolyl group, anisoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinylgroup, a pyridazinyl group, an indolyl group, an isoindolyl group, anindazolyl group, a purinyl group, a quinolinyl group, an isoquinolinylgroup, a benzoquinolinyl group, an isoquinolinyl group, a phthalazinylgroup, a naphthyridinyl group, a quinoxalinyl group, a benzoquinoxalinylgroup, a quinazolinyl group, a benzoquinazolinyl group, a cinnolinylgroup, a phenanthridinyl group, an acridinyl group, a phenanthrolinylgroup, a phenazinyl group, a benzimidazolyl group, a benzofuranyl group,a benzothiophenyl group, a benzosilolyl group, a benzothiazolyl group,an isobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolylgroup, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, atriazinyl group, a carbazolyl group, a dibenzofuranyl group, adibenzothiophenyl group, a dibenzosilolyl group, a benzocarbazolylgroup, a naphthobenzofuranyl group, a naphthobenzothiophenyl group, anaphthobenzosilolyl group, a dibenzocarbazolyl group, a dinaphthofuranylgroup, a dinaphthothiophenyl group, a dinaphthosilolyl group, athiadiazolyl group, an imidazopyridinyl group, an imidazopyrimidinylgroup, an oxazolopyridinyl group, a thiazolopyridinyl group, abenzonaphthyridinyl group, an azafluorenyl group, anazaspiro-bifluorenyl group, an azacarbazolyl group, an azadibenzofuranylgroup, an azadibenzothiophenyl group, an azadibenzosilolyl group, anindenopyrrolyl group, an indolopyrrolyl group, an indeno carbazolylgroup, and an indolocarbazolyl group,

e2 may be an integer selected from 0 to 2,

e3 may be an integer selected from 0 to 3,

e4 may be an integer selected from 0 to 4,

e5 may be an integer selected from 0 to 5,

e6 may be an integer selected from 0 to 6,

e7 may be an integer selected from 0 to 7,

e9 may be an integer selected from 0 to 9, and

* indicates a binding site to a neighboring atom.

For example, in Formula 1, Ar₁ and Ar₂ may each independently beselected from groups represented by Formulae 5-1 to 5-4, 5-7, 5-13,5-14, 5-21 to 5-24, 5-28, 5-76, and 5-80 to 5-83.

In one or more embodiments, in Formula 1, Ar₁ and Ar₂ may eachindependently be selected from groups represented by Formulae 6-1 to6-31:

In Formulae 6-1 to 6-31, * indicates a binding site to a neighboringatom.

In Formula 1, b1 and b2 may each independently be an integer selectedfrom 1 to 5. For example, in Formula 1, b1 and b2 may each independentlybe 1 or 2.

In Formula 1, R₁ and R₂ may each independently be selected fromhydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, an amidino group, a hydrazino group, a hydrazono group, asubstituted or unsubstituted C₁-C₆₀ alkyl group, a substituted orunsubstituted C₂-C₆₀ alkenyl group, a substituted or unsubstitutedC₂-C₆₀ alkynyl group, a substituted or unsubstituted C₁-C₆₀ alkoxygroup, a substituted or unsubstituted C₃-C₁₀ cycloalkyl group, asubstituted or unsubstituted C₁-C₁₀ heterocycloalkyl group, asubstituted or unsubstituted C₃-C₆₀ cycloalkenyl group, a substituted orunsubstituted C₁-C₁₀ heterocycloalkenyl group, a substituted orunsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted C₆-C₆₀aryloxy group, a substituted or unsubstituted C₆-C₆₀ arylthio group, asubstituted or unsubstituted C₁-C₆₀ heteroaryl group, a substituted orunsubstituted monovalent non-aromatic condensed polycyclic group, asubstituted or unsubstituted monovalent non-aromatic condensedheteropolycyclic group, —Si(Q₁)(Q₂)(Q₃), —C(═O)(Q₁), —S(═O)₂(Q₁), and—P(═O)(Q₁)(Q₂).

In an embodiment, in Formula 1, R₁ and R₂ may each independently beselected from:

hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, an amidino group, a hydrazino group, a hydrazono group, aC₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group;

a phenyl group, a biphenyl group, a terphenyl group, a pentalenyl group,an indenyl group, a naphthyl group, an azulenyl group, a heptalenylgroup, an indacenyl group, an acenaphthyl group, a fluorenyl group, aspiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenylgroup, a phenalenyl group, a phenanthrenyl group, an anthracenyl group,a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, achrysenyl group, a naphthacenyl group, a picenyl group, a perylenylgroup, a pentaphenyl group, a hexacenyl group, a pentacenyl group, arubicenyl group, a coronenyl group, an ovalenyl group, a thiophenylgroup, a furanyl group, a carbazolyl group, an indolyl group, anisoindolyl group, a benzofuranyl group, a benzothiophenyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, a dibenzosilolyl group, and apyridinyl group;

a phenyl group, a biphenyl group, a terphenyl group, a pentalenyl group,an indenyl group, a naphthyl group, an azulenyl group, a heptalenylgroup, an indacenyl group, an acenaphthyl group, a fluorenyl group, aspiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenylgroup, a phenalenyl group, a phenanthrenyl group, an anthracenyl group,a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, achrysenyl group, a naphthacenyl group, a picenyl group, a perylenylgroup, a pentaphenyl group, a hexacenyl group, a pentacenyl group, arubicenyl group, a coronenyl group, an ovalenyl group, a thiophenylgroup, a furanyl group, a carbazolyl group, an indolyl group, anisoindolyl group, a benzofuranyl group, a benzothiophenyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, a dibenzosilolyl group, and apyridinyl group, each substituted with at least one selected fromdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a cyclopentyl group, a cyclohexylgroup, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group,a phenyl group, a biphenyl group, a terphenyl group, a phenyl groupsubstituted with a C₁-C₁₀ alkyl group, a phenyl group substituted with—F, a pentalenyl group, an indenyl group, a naphthyl group, an azulenylgroup, a heptalenyl group, an indacenyl group, an acenaphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, ananthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group,a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a rubicenyl group, a coronenyl group, an ovalenyl group, athiophenyl group, a furanyl group, a carbazolyl group, an indolyl group,an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, a dibenzosilolyl group, a pyridinylgroup, and —Si(Q₃₁)(Q₃₂)(Q₃₃); and

—Si(Q₁)(Q₂)(Q₃), and

Q₁ to Q₃ and Q₃₁ to Q₃₃ may each independently be selected from:

a C₁-C₁₀ alkyl group, a C₁-C₁₀ alkoxy group, a phenyl group, a biphenylgroup, a terphenyl group, a naphthyl group, a pyridinyl group, apyrimidinyl group, a pyrazinyl group, a quinolinyl group, anisoquinolinyl group, a quinoxalinyl group, and a quinazolinyl group; and

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, apyridinyl group, a pyrimidinyl group, a pyrazinyl group, a quinolinylgroup, an isoquinolinyl group, a quinoxalinyl group, and a quinazolinylgroup, each substituted with at least one selected from a C₁-C₁₀ alkylgroup, a C₁-C₁₀ alkoxy group, and a phenyl group.

For example, in Formula 1, R₁ and R₂ may each independently be selectedfrom:

hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, an amidino group, a hydrazino group, a hydrazono group, aC₁-C₂₀ alkyl group, and a C₁-C₂₀ alkoxy group;

a C₁-C₂₀ alkyl group and a C₁-C₂₀ alkoxy group, each substituted with atleast one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, acyano group, a nitro group, an amidino group, a hydrazino group, and ahydrazono group;

a cyclopentyl group, a cyclohexyl group, a cyclopentenyl group, acyclohexenyl group, a phenyl group, a biphenyl group, and a terphenylgroup;

a cyclopentyl group, a cyclohexyl group, a cyclopentenyl group, acyclohexenyl group, a phenyl group, a biphenyl group, and a terphenylgroup, each substituted with at least one selected from deuterium, —F,—Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidinogroup, a hydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, aC₁-C₂₀ alkoxy group, a cyclopentyl group, a cyclohexyl group, acyclopentenyl group, a cyclohexenyl group, a phenyl group, a biphenylgroup, and a terphenyl group; and

—Si(Q₁)(Q₂)(Q₃), and

Q₁ to Q₃ may each independently be selected from a C₁-C₂₀ alkyl group, aC₁-C₂₀ alkoxy group, a phenyl group, and a naphthyl group.

In Formula 1, c1 and c2 may each independently be an integer selectedfrom 0 to 7. When c1 is two or more, two or more R₁(s) may be identicalto or different from each other. When c2 is two or more, two or moreR₂(s) may be identical to or different from each other.

In Formula 1, m and n may each independently be an integer selected from0 to 8, wherein the sum of m and n is equal to or greater than 1.

In an embodiment, in Formula 1, the sum of m and n is equal to 1 or 2.

In one or more embodiments, in Formula 1, R₁ and R₂ may eachindependently be selected from:

hydrogen, deuterium. —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, an amidino group, a hydrazino group, a hydrazono group, aC₁-C₂₀ alkyl group, and a C₁-C₂₀ alkoxy group; and

a C₁-C₂₀ alkyl group and a C₁-C₂₀ alkoxy group, each substituted with atleast one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, acyano group, a nitro group, an amidino group, a hydrazino group, and ahydrazono group, and

m and n may each independently satisfy a relationship of m=0 and n=1;m=1 and n=0; m=0 and n=2; m=1 and n=1; or m=2 and n=0.

For example, in Formula 1, R₁ and R₂ may each independently be hydrogen,and

m and n may each independently satisfy a relationship of m=0 and n=1;m=1 and n=0; m=0 and n=2; m=1 and n=1; or m=2 and n=0.

In an embodiment, Formula 1 may be represented by one selected fromFormulae 1-1 to 1-9:

In Formulae 1-1 to 1-9,

descriptions of X, Y, L₁, L₂, a1, a2, Ar₁, Ar₂, b1, b2, R₁, R₂, c1, c2,m, and n are each independently the same as defined above.

In one or more embodiments, Formula 1 may be represented by one selectedfrom Formulae 1-11 to 1-19:

wherein, in Formulae 1-11 to 1-19,

descriptions of R₁₁ to R₁₈ may be the same as defined in connection withR₁, and descriptions of R₂₁ to R₂₈ may be the same as defined inconnection with R₂,

at least one selected from R₁₁ to R₁₄ may be a binding site to a grouprepresented by Formula 2-1, or at least one selected from R₂₁ to R₂₄ maybe a binding site to a group represented by Formula 2-2, and

descriptions of X, Y, L₁, L₂, a1, a2, Ar₁, Ar₂, b1, and b2 may be thesame as defined above.

In an embodiment, Formula 1 may be represented by Formula 1-11,

wherein, in Formula 1-11,

(i) R₁₁ to R₁₄ may each independently be selected from:

hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, an amidino group, a hydrazino group, a hydrazono group, aC₁-C₂₀ alkyl group, and a C₁-C₂₀ alkoxy group; and

a C₁-C₂₀ alkyl group and a C₁-C₂₀ alkoxy group, each substituted with atleast one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, acyano group, a nitro group, an amidino group, a hydrazino group, and ahydrazono group,

R₂₁ to R₂₄ may each independently be selected from:

a group represented by Formula 2-2, hydrogen, deuterium, —F, —Cl, —Br,—I, a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, and a C₁-C₂₀alkoxy group; and

a C₁-C₂₀ alkyl group and a C₁-C₂₀ alkoxy group, each substituted with atleast one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, acyano group, a nitro group, an amidino group, a hydrazino group, and ahydrazono group, and

at least one selected from R₂₁ to R₂₄ may be a group represented byFormula 2-2, or

(ii) R₁₁ to R₁₄ may each independently be selected from:

a group represented by Formula 2-1, hydrogen, deuterium, —F, —Cl, —Br,—I, a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, and a C₁-C₂₀alkoxy group; and

a C₁-C₂₀ alkyl group and a C₁-C₂₀ alkoxy group, each substituted with atleast one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, acyano group, a nitro group, an amidino group, a hydrazino group, and ahydrazono group,

at least one selected from R₁₁ to R₁₄ may be a group represented byFormula 2-1, and

R₂₁ to R₂₄ may each independently be selected from:

hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, an amidino group, a hydrazino group, a hydrazono group, aC₁-C₂₀ alkyl group, and a C₁-C₂₀ alkoxy group; and

a C₁-C₂₀ alkyl group and a C₁-C₂₀ alkoxy group, each substituted with atleast one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, acyano group, a nitro group, an amidino group, a hydrazino group, and ahydrazono group.

In one or more embodiments, Formula 1 may be represented by Formula1-11,

wherein, in Formula 1-11,

R₁₁ to R₁₄ may each independently be selected from:

hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, an amidino group, a hydrazino group, a hydrazono group, aC₁-C₂₀ alkyl group, and a C₁-C₂₀ alkoxy group; and

a C₁-C₂₀ alkyl group and a C₁-C₂₀ alkoxy group, each substituted with atleast one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, acyano group, a nitro group, an amidino group, a hydrazino group, and ahydrazono group,

R₂₁ and R₂₄ may each independently be selected from:

a group represented by Formula 2-2, hydrogen, deuterium, —F, —Cl, —Br,—I, a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, and a C₁-C₂₀alkoxy group; and

a C₁-C₂₀ alkyl group and a C₁-C₂₀ alkoxy group, each substituted with atleast one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, acyano group, a nitro group, an amidino group, a hydrazino group, and ahydrazono group,

at least one selected from R₂₂ and R₂₃ may be a group represented byFormula 2-2.

In an embodiment, the heterocyclic compound represented by Formula 1 maybe one selected from Compounds 1 to 110:

The heterocyclic compound represented by Formula 1 may have a corehaving a structure shown below, and accordingly, condensed rings may beformed with many heteroatoms, which may form a pi-conjugated system withincreased intermolecular packing. In this regard, the heterocycliccompound represented by Formula 1 may have advantages of a high glasstransition temperature, a high melting point, and good chargetransporting capability. Therefore, when the heterocyclic compoundrepresented by Formula 1 is applied to an electronic device, such as anorganic light-emitting device, the electronic device may have highefficiency and a long lifespan:

In addition, in the heterocyclic compound represented by Formula 1,heteroatoms (for example, X and Y) are located at a para-position withrespect to each other, thereby having a molecular structure that maymore easily form hydrogen bonds between molecules. Due to such hydrogenbonds, molecules may be uniformly piled up to increase intermolecularpacking, which may help increase a glass transition temperature and amelting point, and enhance charge transporting capability.

In addition, in the heterocyclic compound represented by Formula 1, thesum of m and n in Formula 1 is equal to or greater than 1, and that is,a substituent other than hydrogen is present. In an implementation, thesubstituent may increase a conjugation length, which may enhance chargetransporting capability.

A synthesis method of the heterocyclic compound represented by Formula 1may be understood by one of skill in the art by referring to Examplesbelow.

A heterocyclic compound represented by Formula 1 may be used between apair of electrodes of an organic light-emitting device. For example, theheterocyclic compound represented by Formula 1 may be included in atleast one layer selected from a hole transport region, an electrontransport region, and an emission layer. In one or more embodiments, theheterocyclic compound represented by Formula 1 may be used as a materialfor a capping layer located outside a pair of electrodes of an organiclight-emitting device.

According to another aspect of embodiments, there is provided an organiclight-emitting device including: a first electrode; a second electrodefacing the first electrode; and an organic layer between the firstelectrode and the second electrode and including an emission layer,wherein the organic layer comprises at least one heterocyclic compoundaccording to an embodiment.

The expression “(an organic layer) includes at least one heterocycliccompound” used herein includes a case in which “(an organic layer)includes identical heterocyclic compounds represented by Formula 1” or acase in which “(an organic layer) includes two or more differentheterocyclic compounds”.

In an example embodiment, the first electrode may be an anode, thesecond electrode may be a cathode, and the organic layer may furtherinclude a hole transport region between the first electrode and theemission layer and an electron transport region between the emissionlayer and the second electrode, wherein the hole transport region mayinclude a hole injection layer, a hole transport layer, an emissionauxiliary layer, an electron blocking layer, or a combination thereof,and the electron transport region may include a buffer layer, a holeblocking layer, an electron control layer, an electron transport layer,an electron injection layer, or a combination thereof.

In an embodiment, the electron transport region may include the at leastone heterocyclic compound represented by Formula 1.

In an embodiment, the electron transport region may include an electrontransport layer, and the electron transport layer may include the atleast one heterocyclic compound represented by Formula 1.

In one or more embodiments, the electron transport region may include anemission auxiliary layer, and the emission auxiliary layer may includethe at least one heterocyclic compound represented by Formula 1.

For example, the hole transport region may include a p-dopant, wherein alowest unoccupied molecular orbital (LUMO) energy level of the p-dopantis equal to or less than about −3.5 eV. The p-dopant may include, forexample, a quinone derivative, a metal oxide, a cyano group-containingcompound, or a combination thereof.

For example, the electron transport region may include an alkali metal,an alkaline earth metal, a rare earth metal, an alkali metal compound,an alkaline earth metal compound, a rare earth metal compound, an alkalimetal complex, an alkaline earth metal complex, a rare earth metalcomplex, or a combination thereof.

For example, the emission layer may include a dopant and a host, whereinthe host may include at least one selected from an anthracene-basedcompound, a pyrene-based compound, and a spiro-bifluorene-basedcompound.

In the organic light-emitting device, the emission layer may include afirst color light emission layer,

the emission layer in the organic light-emitting device may furtherinclude i) at least one second color light emission layer or ii) atleast one second color light emission layer and at least one third colorlight emission layer, between the first electrode and the secondelectrode,

wherein a maximum emission wavelength of the first color light emissionlayer, a maximum emission wavelength of the second color light emissionlayer, and a maximum emission wavelength of the third color lightemission layer may be identical to or different from each other, and

the first color light and the second color light may be emitted as mixedlight, or the first color light, the second color light, and the thirdcolor light may be emitted as mixed light.

The organic light-emitting device may further include at least oneselected from a first capping layer disposed in a pathway along whichlight generated in the emission layer proceeds toward the outsidethrough the first electrode and a second capping layer disposed in apathway along which light generated in the emission layer proceedstoward the outside through the second electrode, wherein at least one ofthe first capping layer and the second capping layer may include the atleast one heterocyclic compound represented by Formula 1.

For example, the organic light-emitting device may have i) a stackstructure including a first electrode, an organic layer, a secondelectrode, and a second capping layer which are sequentially stacked inthis stated order, ii) a stack structure including a first cappinglayer, a first electrode, an organic layer, and a second electrode whichare sequentially stacked in this stated order, or iii) a stack structureincluding a first capping layer, a first electrode, an organic layer, asecond electrode, and a second capping layer which are sequentiallystacked in this stated order, wherein, in each structure, at least oneof the first capping layer and the second capping layer may include theat least one heterocyclic compound represented by Formula 1.

The term “organic layer” used herein refers to a single layer and/or aplurality of layers disposed between the first electrode and the secondelectrode of the organic light-emitting device. A material included inthe “organic layer” is not limited to an organic material.

[Description of FIG. 1]

FIG. 1 is a schematic view of an organic light-emitting device 10according to an embodiment. The organic light-emitting device 10includes a first electrode 110, an organic layer 150, and a secondelectrode 190.

Hereinafter, the structure of the organic light-emitting device 10according to an embodiment and a method of manufacturing the organiclight-emitting device 10 will be described in connection with FIG. 1.

[First Electrode 110]

In FIG. 1, a substrate may be additionally disposed under the firstelectrode 110 or above the second electrode 190. The substrate may be,for example, a glass substrate or a plastic substrate, which may haveexcellent mechanical strength, thermal stability, transparency, surfacesmoothness, ease of handling, and water resistance.

The first electrode 110 may be formed by, for example, depositing orsputtering a material for forming the first electrode 110 on thesubstrate. When the first electrode 110 is an anode, the material forforming the first electrode 110 may be selected from, for example,materials with a high work function to facilitate hole injection.

The first electrode 110 may be, for example, a reflective electrode, asemi-transmissive electrode, or a transmissive electrode. When the firstelectrode 110 is a transmissive electrode, the material for forming thefirst electrode 110 may be selected from, for example, indium tin oxide(ITO), indium zinc oxide (IZO), tin oxide (SnO₂), zinc oxide (ZnO), anda combination thereof. In one or more embodiments, when the firstelectrode 110 is a semi-transmissive electrode or a reflectiveelectrode, the material for forming the first electrode 110 may beselected from, for example, magnesium (Mg), silver (Ag), aluminum (Al),aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In),magnesium-silver (Mg—Ag), and a combination thereof.

The first electrode 110 may have, for example, a single-layeredstructure, or a multi-layered structure including two or more layers.For example, the first electrode 110 may have a three-layered structureof ITO/Ag/ITO.

[Organic Layer 150]

The organic layer 150 may be disposed on the first electrode 110. Theorganic layer 150 may include an emission layer.

The organic layer 150 may further include a hole transport regionbetween the first electrode 110 and the emission layer, and an electrontransport region between the emission layer and the second electrode190.

[Hole Transport Region in Organic Layer 150]

The hole transport region may have, for example, i) a single-layeredstructure including a single layer including a single material, ii) asingle-layered structure including a single layer including a pluralityof different materials, or iii) a multi-layered structure having aplurality of layers including a plurality of different materials.

The hole transport region may include at least one layer selected from ahole injection layer, a hole transport layer, an emission auxiliarylayer, and an electron blocking layer.

For example, the hole transport region may have a single-layeredstructure including a single layer including a plurality of differentmaterials, or a multi-layered structure having a hole injectionlayer/hole transport layer structure, a hole injection layer/holetransport layer/emission auxiliary layer structure, a hole injectionlayer/emission auxiliary layer structure, a hole transportlayer/emission auxiliary layer structure, or a hole injection layer/holetransport layer/electron blocking layer structure, wherein, for eachstructure, constituting layers are sequentially stacked from the firstelectrode 110 in this stated order, but the structure of the holetransport region is not limited thereto.

The hole transport region may include at least one selected fromm-MTDATA, TDATA, 2-TNATA, NPB(NPD), β-NPB, TPD, spiro-TPD, spiro-NPB,methylated-NPB, TAPC, HMTPD, 4,4′,4″-tris(N-carbazolyl)triphenylamine(TCTA), polyaniline/dodecylbenzenesulfonic acid (PANI/DBSA),poly(3,4-ethylenedioxythiophene)/poly(4-styrenesulfonate) (PEDOT/PSS),polyaniline/camphor sulfonic acid (PANI/CSA),polyaniline/poly(4-styrenesulfonate) (PANI/PSS), a compound representedby Formula 201, and a compound represented by Formula 202:

In Formulae 201 and 202,

L₂₀₁ to L₂₀₄ may each independently be selected from a substituted orunsubstituted C₃-C₁₀ cycloalkylene group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkylene group, a substituted or unsubstituted C₃-C₁₀cycloalkenylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenylene group, a substituted or unsubstituted C₆-C₆₀arylene group, a substituted or unsubstituted C₁-C₆₀ heteroarylenegroup, a substituted or unsubstituted divalent non-aromatic condensedpolycyclic group, and a substituted or unsubstituted divalentnon-aromatic condensed heteropolycyclic group;

L₂₀₅ may be selected from *—O—*′, *—S—*′, *—N(Q₂₀₁)-*′, a substituted orunsubstituted C₁-C₂₀ alkylene group, a substituted or unsubstitutedC₂-C₂₀ alkenylene group, a substituted or unsubstituted C₃-C₁₀cycloalkylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkylene group, a substituted or unsubstituted C₃-C₁₀cycloalkenylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenylene group, a substituted or unsubstituted C₆-C₆₀arylene group, a substituted or unsubstituted C₁-C₆₀ heteroarylenegroup, a substituted or unsubstituted divalent non-aromatic condensedpolycyclic group, and a substituted or unsubstituted divalentnon-aromatic condensed heteropolycyclic group,

xa1 to xa4 may each independently be an integer of 0 to 3,

xa5 may be an integer of 1 to 10, and

R₂₀₁ to R₂₀₄ and Q₂₀₁ may each independently be selected from asubstituted or unsubstituted C₃-C₁₀ cycloalkyl group, a substituted orunsubstituted C₁-C₁₀ heterocycloalkyl group, a substituted orunsubstituted C₃-C₁₀ cycloalkenyl group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀aryl group, a substituted or unsubstituted C₆-C₆₀ aryloxy group, asubstituted or unsubstituted C₆-C₆₀ arylthio group, a substituted orunsubstituted C₁-C₆₀ heteroaryl group, a substituted or unsubstitutedmonovalent non-aromatic condensed polycyclic group, and a substituted orunsubstituted monovalent non-aromatic condensed heteropolycyclic group.

In an embodiment, in Formula 202, R₂₀₁ and R₂₀₂ may optionally be linkedvia a single bond, a dimethyl-methylene group, or a diphenyl-methylenegroup, and R₂₀₃ and R₂₀₄ may optionally be linked via a single bond, adimethyl-methylene group, or a diphenyl-methylene group.

In one or more embodiments, in Formulae 201 and 202,

L₂₀₁ to L₂₀₅ may each independently be selected from:

a phenylene group, a pentalenylene group, an indenylene group, anaphthylene group, an azulenylene group, a heptalenylene group, anindacenylene group, an acenaphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenalenylene group, a phenanthrenylenegroup, an anthracenylene group, a fluoranthenylene group, atriphenylenylene group, a pyrenylene group, a chrysenylene group, anaphthacenylene group, a picenylene group, a perylenylene group, apentaphenylene group, a hexacenylene group, a pentacenylene group, arubicenylene group, a coronenylene group, an ovalenylene group, athiophenylene group, a furanylene group, a carbazolylene group, anindolylene group, an isoindolylene group, a benzofuranylene group, abenzothiophenylene group, a dibenzofuranylene group, adibenzothiophenylene group, a benzocarbazolylene group, adibenzocarbazolylene group, a dibenzosilolylene group, and apyridinylene group; and

a phenylene group, a pentalenylene group, an indenylene group, anaphthylene group, an azulenylene group, a heptalenylene group, anindacenylene group, an acenaphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenalenylene group, a phenanthrenylenegroup, an anthracenylene group, a fluoranthenylene group, atriphenylenylene group, a pyrenylene group, a chrysenylene group, anaphthacenylene group, a picenylene group, a perylenylene group, apentaphenylene group, a hexacenylene group, a pentacenylene group, arubicenylene group, a coronenylene group, an ovalenylene group, athiophenylene group, a furanylene group, a carbazolylene group, anindolylene group, an isoindolylene group, a benzofuranylene group, abenzothiophenylene group, a dibenzofuranylene group, adibenzothiophenylene group, a benzocarbazolylene group, adibenzocarbazolylene group, a dibenzosilolylene group, and apyridinylene group, each substituted with at least one selected fromdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a cyclopentyl group, a cyclohexylgroup, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group,a phenyl group, a biphenyl group, a terphenyl group, a phenyl groupsubstituted with a C₁-C₁₀ alkyl group, a phenyl group substituted with—F, a pentalenyl group, an indenyl group, a naphthyl group, an azulenylgroup, a heptalenyl group, an indacenyl group, an acenaphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, ananthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group,a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a rubicenyl group, a coronenyl group, an ovalenyl group, athiophenyl group, a furanyl group, a carbazolyl group, an indolyl group,an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, a dibenzosilolyl group, a pyridinylgroup, —Si(Q₃₁)(Q₃₂)(Q₃₃) and —N(Q₃₁)(Q₃₂), and

Q₃₁ to Q₃₃ may each independently be selected from a C₁-C₁₀ alkyl group,a C₁-C₁₀ alkoxy group, a phenyl group, a biphenyl group, a terphenylgroup, and a naphthyl group.

In one or more embodiments, xa1 to xa4 may each independently be 0, 1,or 2.

In one or more embodiments, xa5 may be 1, 2, 3, or 4.

In one or more embodiments, R₂₀₁ to R₂₀₄ and Q₂₀₁ may each independentlybe selected from a phenyl group, a biphenyl group, a terphenyl group, apentalenyl group, an indenyl group, a naphthyl group, an azulenyl group,a heptalenyl group, an indacenyl group, an acenaphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, ananthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group,a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a rubicenyl group, a coronenyl group, an ovalenyl group, athiophenyl group, a furanyl group, a carbazolyl group, an indolyl group,an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, a dibenzosilolyl group, and apyridinyl group; and

a phenyl group, a biphenyl group, a terphenyl group, a pentalenyl group,an indenyl group, a naphthyl group, an azulenyl group, a heptalenylgroup, an indacenyl group, an acenaphthyl group, a fluorenyl group, aspiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenylgroup, a phenalenyl group, a phenanthrenyl group, an anthracenyl group,a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, achrysenyl group, a naphthacenyl group, a picenyl group, a perylenylgroup, a pentaphenyl group, a hexacenyl group, a pentacenyl group, arubicenyl group, a coronenyl group, an ovalenyl group, a thiophenylgroup, a furanyl group, a carbazolyl group, an indolyl group, anisoindolyl group, a benzofuranyl group, a benzothiophenyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, a dibenzosilolyl group, and apyridinyl group, each substituted with at least one selected fromdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a cyclopentyl group, a cyclohexylgroup, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group,a phenyl group, a biphenyl group, a terphenyl group, a phenyl groupsubstituted with a C₁-C₁₀ alkyl group, a phenyl group substituted with—F, a pentalenyl group, an indenyl group, a naphthyl group, an azulenylgroup, a heptalenyl group, an indacenyl group, an acenaphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, ananthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group,a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a rubicenyl group, a coronenyl group, an ovalenyl group, athiophenyl group, a furanyl group, a carbazolyl group, an indolyl group,an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, a dibenzosilolyl group, a pyridinylgroup, —Si(Q₃₁)(Q₃₂)(Q₃₃), and —N(Q₃₁)(Q₃₂), and

descriptions of Q₃₁ to Q₃₃ are the same as defined above.

In one or more embodiments, in Formula 201, at least one selected fromR₂₀₁ to R₂₀₃ may each independently be selected from:

a fluorenyl group, a spiro-bifluorenyl group, a carbazolyl group, adibenzofuranyl group, and a dibenzothiophenyl group; and

a fluorenyl group, a spiro-bifluorenyl group, a carbazolyl group, adibenzofuranyl group, and a dibenzothiophenyl group, each substitutedwith at least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxylgroup, a cyano group, a nitro group, an amidino group, a hydrazinogroup, a hydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, acyclopentyl group, a cyclohexyl group, a cycloheptyl group, acyclopentenyl group, a cyclohexenyl group, a phenyl group, a biphenylgroup, a terphenyl group, a phenyl group substituted with a C₁-C₁₀ alkylgroup, a phenyl group substituted with —F, a naphthyl group, a fluorenylgroup, a spiro-bifluorenyl group, a carbazolyl group, a dibenzofuranylgroup, and a dibenzothiophenyl group.

In one or more embodiments, in Formula 202, i) R₂₀₁ and R₂₀₂ may belinked via a single bond and/or ii) R₂₀₃ and R₂₀₄ may be linked via asingle bond.

In one or more embodiments, in Formula 202, at least one selected fromR₂₀₁ to R₂₀₄ may be selected from:

a carbazolyl group; and

a carbazolyl group substituted with at least one selected fromdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a cyclopentyl group, a cyclohexylgroup, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group,a phenyl group, a biphenyl group, a terphenyl group, a phenyl groupsubstituted with a C₁-C₁₀ alkyl group, a phenyl group substituted with—F, a naphthyl group, a fluorenyl group, a spiro-bifluorenyl group, acarbazolyl group, a dibenzofuranyl group, and a dibenzothiophenyl group.

The compound represented by Formula 201 may be represented by Formula201A:

In an embodiment, the compound represented by Formula 201 may berepresented by Formula 201A(1) below:

In an embodiment, the compound represented by Formula 201 may berepresented by Formula 201A-1 below:

In an embodiment, the compound represented by Formula 202 may berepresented by Formula 202A:

In an embodiment, the compound represented by Formula 202 may berepresented by Formula 202A-1:

In Formulae 201A, 201A(1), 201A-1, 202A, and 202A-1,

descriptions of L₂₀₁ to L₂₀₃, xa1 to xa3, xa5, and R₂₀₂ to R₂₀₄ are eachthe same as defined above,

descriptions of R₂₁₁ and R₂₁₂ are each the same as defined in connectionwith R₂₀₃,

R₂₁₃ to R₂₁₇ may each independently be selected from hydrogen,deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a cyclopentyl group, a cyclohexylgroup, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group,a phenyl group, a biphenyl group, a terphenyl group, a phenyl groupsubstituted with a C₁-C₁₀ alkyl group, a phenyl group substituted with—F, a pentalenyl group, an indenyl group, a naphthyl group, an azulenylgroup, a heptalenyl group, an indacenyl group, an acenaphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, ananthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group,a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a rubicenyl group, a coronenyl group, an ovalenyl group, athiophenyl group, a furanyl group, a carbazolyl group, an indolyl group,an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, a dibenzosilolyl group, and apyridinyl group.

The hole transport region may include at least one compound selectedfrom Compounds HT1 to HT39:

A thickness of the hole transport region may be in a range of, forexample, about 100 Å to about 10,000 Å, for example, about 100 Å toabout 1,000 Å. When the hole transport region includes at least one of ahole injection layer and a hole transport layer, a thickness of the holeinjection layer may be in a range of, for example, about 100 Å to about9,000 Å, for example, about 100 Å to about 1,000 Å, and a thickness ofthe hole transport layer may be in a range of, for example, about 50 Åto about 2,000 Å, for example about 100 Å to about 1,500 Å. When thethicknesses of the hole transport region, the hole injection layer andthe hole transport layer are within these ranges, satisfactory holetransporting characteristics may be obtained without a substantialincrease in driving voltage.

The emission auxiliary layer may increase light-emission efficiency bycompensating for an optical resonance distance according to thewavelength of light emitted by an emission layer, and the electronblocking layer may block the flow of electrons from an electrontransport region. The emission auxiliary layer and the electron blockinglayer may include the materials as described above.

[P-Dopant]

The hole transport region may further include, in addition to thesematerials, a charge-generation material for improving conductiveproperties. The charge-generation material may be homogeneously ornon-homogeneously dispersed in the hole transport region.

The charge-generation material may be, for example, a p-dopant.

In an embodiment, a LUMO energy level of the p-dopant may be −3.5 eV orless.

The p-dopant may include, for example, at least one selected from aquinone derivative, a metal oxide, and a cyano group-containingcompound.

For example, the p-dopant may include at least one selected from

a quinone derivative, such as tetracyanoquinodimethane (TCNQ) or2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4-TCNQ);

a metal oxide, such as tungsten oxide or molybdenum oxide;

1,4,5,8,9,11-hexaazatriphenylene-hexacarbonitrile (HAT-CN); and

a compound represented by Formula 221 below:

In Formula 221,

R₂₂₁ to R₂₂₃ may each independently be selected from a substituted orunsubstituted C₃-C₆₀ cycloalkyl group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀cycloalkenyl group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀ arylgroup, a substituted or unsubstituted C₁-C₆₀ heteroaryl group, asubstituted or unsubstituted monovalent non-aromatic condensedpolycyclic group, and a substituted or unsubstituted monovalentnon-aromatic condensed heteropolycyclic group, wherein at least oneselected from R₂₂₁ to R₂₂₃ may have at least one substituent selectedfrom a cyano group, —F, —Cl, —Br, —I, a C₁-C₂₀ alkyl group substitutedwith —F, a C₁-C₂₀ alkyl group substituted with —Cl, a C₁-C₂₀ alkyl groupsubstituted with —Br and a C₁-C₂₀ alkyl group substituted with —I.

[Emission Layer in Organic Layer 150]

When the organic light-emitting device 10 is a full-color organiclight-emitting device, the emission layer may be patterned into, forexample, a red emission layer, a green emission layer, or a blueemission layer, according to a sub-pixel. In one or more embodiments,the emission layer may have a stacked structure of two or more layersselected from a red emission layer, a green emission layer, and a blueemission layer, in which the two or more layers contact each other orare separated from each other. In one or more embodiments, the emissionlayer may be patterned into a red light-emitting material, a green-lightemitting material, and a blue-light emitting material, in which two ormore materials are mixed with each other in a single layer to emit whitecolor.

The emission layer may include, for example, a host and a dopant. Thedopant may include, for example, at least one of a phosphorescent dopantand a fluorescent dopant.

An amount of the dopant in the emission layer may be, for example, in arange of about 0.01 parts by weight to about 15 parts by weight based on100 parts by weight of the host.

A thickness of the emission layer may be in a range of, for example,about 100 Å to about 1,000 Å, for example, about 200 Å to about 600 Å.When thickness of the emission layer is within this range, excellentlight-emission characteristics may be obtained without a substantialincrease in driving voltage.

[Host in Emission Layer]

In one or more embodiments, the host may include a compound representedby Formula 301 below.

[Ar₃₀₁]_(xb11)-[(L₃₀₁)_(xb1)-R₃₀₁]_(xb21).  <Formula 301>

In Formula 301,

Ar₃₀₁ may be a substituted or unsubstituted C₅-C₆₀ carbocyclic group ora substituted or unsubstituted C₁-C₆₀ heterocyclic group,

xb11 may be 1, 2, or 3,

L₃₀₁ may be selected from a substituted or unsubstituted C₃-C₁₀cycloalkylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkylene group, a substituted or unsubstituted C₃-C₁₀cycloalkenylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenylene group, a substituted or unsubstituted C₆-C₆₀arylene group, a substituted or unsubstituted C₁-C₆₀ heteroarylenegroup, a substituted or unsubstituted divalent non-aromatic condensedpolycyclic group, and a substituted or unsubstituted divalentnon-aromatic condensed heteropolycyclic group,

xb1 may be an integer of 0 to 5,

R₃₀₁ may be selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group,a cyano group, a nitro group, an amidino group, a hydrazino group, ahydrazono group, a substituted or unsubstituted C₁-C₆₀ alkyl group, asubstituted or unsubstituted C₂-C₆₀ alkenyl group, a substituted orunsubstituted C₂-C₆₀ alkynyl group, a substituted or unsubstitutedC₁-C₆₀ alkoxy group, a substituted or unsubstituted C₃-C₁₀ cycloalkylgroup, a substituted or unsubstituted C₁-C₁₀ heterocycloalkyl group, asubstituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a substituted orunsubstituted C₁-C₁₀ heterocycloalkenyl group, a substituted orunsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted C₆-C₆₀aryloxy group, a substituted or unsubstituted C₆-C₆₀ arylthio group, asubstituted or unsubstituted C₁-C₆₀ heteroaryl group, a substituted orunsubstituted monovalent non-aromatic condensed polycyclic group, asubstituted or unsubstituted monovalent non-aromatic condensedheteropolycyclic group, —Si(Q₃₀₁)(Q₃₀₂)(Q₃₀₃), —N(Q₃₀₁)(Q₃₀₂),—B(Q₃₀₁₎(Q₃₀₂), —C(═O)(Q₃₀₁), —S(═O)₂(Q₃₀₁), and —P(═O)(Q₃₀₁)(Q₃₀₂),

xb21 may be an integer from 1 to 5, and

Q₃₀₁ to Q₃₀₃ may each independently be selected from a C₁-C₁₀ alkylgroup, a C₁-C₁₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, and a naphthyl group.

In an embodiment, Ar₃₀₁ in Formula 301 may be selected from:

a naphthalene group, a fluorene group, a spiro-bifluorene group, abenzofluorene group, a dibenzofluorene group, a phenalene group, aphenanthrene group, an anthracene group, a fluoranthene group, atriphenylene group, a pyrene group, a chrysene group, a naphthacenegroup, a picene group, a perylene group, a pentaphene group, anindenoanthracene group, a dibenzofuran group, and a dibenzothiophenegroup; and

a naphthalene group, a fluorene group, a spiro-bifluorene group, abenzofluorene group, a dibenzofluorene group, a phenalene group, aphenanthrene group, an anthracene group, a fluoranthene group, atriphenylene group, a pyrene group, a chrysene group, a naphthacenegroup, a picene group, a perylene group, a pentaphene group, anindenoanthracene group, a dibenzofuran group, and a dibenzothiophenegroup, each substituted with at least one selected from deuterium, —F,—Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidinogroup, a hydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, aC₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, a terphenylgroup, a naphthyl group, —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂),—C(═O)(Q₃₁), —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), and

Q₃₁ to Q₃₃ may each independently be selected from a C₁-C₁₀ alkyl group,a C₁-C₁₀ alkoxy group, a phenyl group, a biphenyl group, a terphenylgroup, and a naphthyl group.

When xb11 in Formula 301 is two or more, two or more Ar₃₀₁(s) may belinked via a single bond.

In one or more embodiments, the compound represented by Formula 301 maybe represented by Formula 301-1 or 301-2:

wherein, in Formulae 301-1 and 301-2,

A₃₀₁ to A₃₀₄ may each independently be selected from a benzene group, anaphthalene group, a phenanthrene group, a fluoranthene group, atriphenylene group, a pyrene group, a chrysene group, a pyridine group,a pyrimidine group, an indene group, a fluorene group, aspiro-bifluorene group, a benzofluorene group, a dibenzofluorene group,an indole group, a carbazole group, a benzocarbazole group, adibenzocarbazole group, a furan group, a benzofuran group, adibenzofuran group, a naphthofuran group, a benzonaphthofuran group,dinaphthofuran group, a thiophene group, a benzothiophene group, adibenzothiophene group, a naphthothiophene group, abenzonaphthothiophene group, and a dinaphthothiophene group.

X₃₀₁ may be O, S, or N-[(L₃₀₄)_(xb4)-R₃₀₄],

R₃₁₁ to R₃₁₄ may each independently be selected from hydrogen,deuterium. —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, a naphthyl group —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂),—B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁), —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂),

xb22 and xb23 may each independently be 0, 1, or 2,

descriptions of L₃₀₁, xb1, R₃₀₁, and Q₃₁ to Q₃₃ are the same as definedabove,

descriptions of L₃₀₂ to L₃₀₄ are the same as defined in connection withL₃₀₁,

descriptions of xb2 to xb4 are the same as defined in connection withxb1, and

descriptions of R₃₀₂ to R₃₀₄ are the same as defined in connection withR₃₀₁.

For example, in Formulae 301, 301-1, and 301-2, L₃₀₁ to L₃₀₄ may eachindependently be selected from:

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a fluoranthenylene group, a triphenylenylene group, a pyrenylenegroup, a chrysenylene group, a perylenylene group, a pentaphenylenegroup, a hexacenylene group, a pentacenylene group, a thiophenylenegroup, a furanylene group, a carbazolylene group, an indolylene group,an isoindolylene group, a benzofuranylene group, a benzothiophenylenegroup, a dibenzofuranylene group, a dibenzothiophenylene group, abenzocarbazolylene group, a dibenzocarbazolylene group, adibenzosilolylene group, a pyridinylene group, an imidazolylene group, apyrazolylene group, a thiazolylene group, an isothiazolylene group, anoxazolylene group, an isoxazolylene group, a thiadiazolylene group, anoxadiazolylene group, a pyrazinylene group, a pyrimidinylene group, apyridazinylene group, a triazinylene group, a quinolinylene group, anisoquinolinylene group, a benzoquinolinylene group, a phthalazinylenegroup, a naphthyridinylene group, a quinoxalinylene group, aquinazolinylene group, a cinnolinylene group, a phenanthridinylenegroup, an acridinylene group, a phenanthrolinylene group, aphenazinylene group, a benzimidazolylene group, an isobenzothiazolylenegroup, a benzoxazolylene group, an isobenzoxazolylene group, atriazolylene group, a tetrazolylene group, an imidazopyridinylene group,an imidazopyrimidinylene group, and an azacarbazolylene group; and

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a fluoranthenylene group, a triphenylenylene group, a pyrenylenegroup, a chrysenylene group, a perylenylene group, a pentaphenylenegroup, a hexacenylene group, a pentacenylene group, a thiophenylenegroup, a furanylene group, a carbazolylene group, an indolylene group,an isoindolylene group, a benzofuranylene group, a benzothiophenylenegroup, a dibenzofuranylene group, a dibenzothiophenylene group, abenzocarbazolylene group, a dibenzocarbazolylene group, adibenzosilolylene group, a pyridinylene group, an imidazolylene group, apyrazolylene group, a thiazolylene group, an isothiazolylene group, anoxazolylene group, an isoxazolylene group, a thiadiazolylene group, anoxadiazolylene group, a pyrazinylene group, a pyrimidinylene group, apyridazinylene group, a triazinylene group, a quinolinylene group, anisoquinolinylene group, a benzoquinolinylene group, a phthalazinylenegroup, a naphthyridinylene group, a quinoxalinylene group, aquinazolinylene group, a cinnolinylene group, a phenanthridinylenegroup, an acridinylene group, a phenanthrolinylene group, aphenazinylene group, a benzimidazolylene group, an isobenzothiazolylenegroup, a benzoxazolylene group, an isobenzoxazolylene group, atriazolylene group, a tetrazolylene group, an imidazopyridinylene group,an imidazopyrimidinylene group, and an azacarbazolylene group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, anaphthyl group, a fluorenyl group, a spiro-bifluorenyl group, abenzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group,an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a perylenyl group, a pentaphenylgroup, a hexacenyl group, a pentacenyl group, a thiophenyl group, afuranyl group, a carbazolyl group, an indolyl group, an isoindolylgroup, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranylgroup, a dibenzothiophenyl group, a benzocarbazolyl group, adibenzocarbazolyl group, a dibenzosilolyl group, a pyridinyl group, animidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolylgroup, an oxazolyl group, an isoxazolyl group, a thiadiazolyl group, anoxadiazolyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a triazinyl group, a quinolinyl group, an isoquinolinyl group, abenzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, aquinoxalinyl group, a quinazolinyl group, a cinnolinyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, aphenazinyl group, a benzimidazolyl group, an isobenzothiazolyl group, abenzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, atetrazolyl group, an imidazopyridinyl group, an imidazopyrimidinylgroup, an azacarbazolyl group, —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂),—B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁), —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), and

descriptions of Q₃₁ to Q₃₃ are the same as defined above.

In an embodiment, in Formulae 301, 301-1, and 301-2, R₃₀₁ to R₃₀₄ mayeach independently be selected from:

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, an imidazolyl group, apyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolylgroup, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group,a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinylgroup, a quinolinyl group, an isoquinolinyl group, a benzoquinolinylgroup, a phthalazinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a cinnolinyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolylgroup, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group,an imidazopyridinyl group, an imidazopyrimidinyl group, and anazacarbazolyl group; and

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, an imidazolyl group, apyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolylgroup, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group,a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinylgroup, a quinolinyl group, an isoquinolinyl group, a benzoquinolinylgroup, a phthalazinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a cinnolinyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolylgroup, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group,an imidazopyridinyl group, an imidazopyrimidinyl group, and anazacarbazolyl group, each substituted with at least one selected fromdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, a naphthyl group, a fluorenyl group, aspiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenylgroup, a phenanthrenyl group, an anthracenyl group, a fluoranthenylgroup, a triphenylenyl group, a pyrenyl group, a chrysenyl group, aperylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a thiophenyl group, a furanyl group, a carbazolyl group, anindolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, an imidazolyl group, apyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolylgroup, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group,a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinylgroup, a quinolinyl group, an isoquinolinyl group, a benzoquinolinylgroup, a phthalazinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a cinnolinyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolylgroup, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group,an imidazopyridinyl group, an imidazopyrimidinyl group, an azacarbazolylgroup, —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁),—S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), and

descriptions of Q₃₁ to Q₃₃ are the same as defined above.

In one or more embodiments, the host may include, for example, analkaline earth metal complex. For example, the host may be selected froma beryllium (Be) complex (for example, Compound H55), an Mg complex, anda Zn complex.

The host may include, for example, at least one selected from9,10-di(2-naphthyl)anthracene (ADN),2-methyl-9,10-bis(naphthalen-2-yl)anthracene (MADN),9,10-di-(2-naphthyl)-2-t-butyl-anthracene (TBADN),4,4′-bis(N-carbazolyl)-1,1′-biphenyl (CBP), 1,3-di-9-carbazolylbenzene(mCP), 1,3,5-tri(carbazol-9-yl)benzene (TCP), and Compounds H1 to H55:

[Phosphorescent Dopant Included in Emission Layer in Organic Layer 150]

The phosphorescent dopant may include, for example, an organometalliccomplex represented by Formula 401 below:

In Formulae 401 and 402,

M may be selected from iridium (Ir), platinum (Pt), palladium (Pd),osmium (Os), titanium (Ti), zirconium (Zr), hafnium (Hf), europium (Eu),terbium (Tb), rhodium (Rh), and thulium (Tm),

L₄₀₁ may be selected from ligands represented by Formula 402, and xc1may be 1, 2, or 3, wherein, when xc1 is two or more, two or more L₄₀₁(s)may be identical to or different from each other,

L₄₀₂ may be an organic ligand, and xc2 may be an integer of 0 to 4,wherein, when xc2 is two or more, two or more L₄₀₂(s) may be identicalto or different from each other,

X₄₀₁ to X₄₀₄ may each independently be nitrogen or carbon,

X₄₀₁ and X₄₀₃ may be linked via a single bond or a double bond, and X₄₀₂and X₄₀₄ may be linked via a single bond or a double bond,

A₄₀₁ and A₄₀₂ may each independently be a C₅-C₆₀ carbocyclic group or aC₁-C₆₀ heterocyclic group,

X₄₀₅ may be a single bond, *—O—*′, *—S—*′, *—C(═O)—*′, *—N(Q₄₁₁)-*′,*—C(Q₄₁₁)(Q₄₁₂)-*′, *—C(Q₄₁₁)=C(Q₄₁₂)-*′, *—C(Q₄₁₁)═*′, or *═C═*′,wherein Q₄₁₁ and Q₄₁₂ may each independently be hydrogen, deuterium, aC₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenylgroup, a terphenyl group, or a naphthyl group.

X₄₀₆ may be a single bond, O, or S.

R₄₀₁ and R₄₀₂ may each independently be selected from hydrogen,deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, asubstituted or unsubstituted C₁-C₂₀ alkyl group, a substituted orunsubstituted C₁-C₂₀ alkoxy group, a substituted or unsubstituted C₃-C₁₀cycloalkyl group, a substituted or unsubstituted C₁-C₁₀ heterocycloalkylgroup, a substituted or unsubstituted C₃-C₁₀ cycloalkenyl group, asubstituted or unsubstituted C₁-C₁₀ heterocycloalkenyl group, asubstituted or unsubstituted C₆-C₆₀ aryl group, a substituted orunsubstituted C₆-C₆₀ aryloxy group, a substituted or unsubstitutedC₆-C₆₀ arylthio group, a substituted or unsubstituted C₁-C₆₀ heteroarylgroup, a substituted or unsubstituted monovalent non-aromatic condensedpolycyclic group, and a substituted or unsubstituted monovalentnon-aromatic condensed heteropolycyclic group, —Si(Q₄₀₁)(Q₄₀₂)(Q₄₀₃),—N(Q₄₀₁)(Q₄₀₂), —B(Q₄₀₁)(Q₄₀₂), —C(═O)(Q₄₀₁), —S(═O)₂(Q₄₀₁), and—P(═O)(Q₄₀₁)(Q₄₀₂),

Q₄₀₁ to Q₄₀₃ may each independently be selected from a C₁-C₁₀ alkylgroup, a C₁-C₁₀ alkoxy group, a C₆-C₂₀ aryl group, and a C₁-C₂₀heteroaryl group,

xc11 and xc12 may each independently be an integer of 0 to 10, and

in Formula 402, * and *′ each indicate a binding site to M in Formula401.

In an embodiment, in Formula 402, A₄₀₁ and A₄₀₂ may each independentlybe selected from a benzene group, a naphthalene group, a fluorene group,a spiro-bifluorene group, an indene group, a pyrrole group, a thiophenegroup, a furan group, an imidazole group, a pyrazole group, a thiazolegroup, an isothiazole group, an oxazole group, an isoxazole group, apyridine group, a pyrazine group, a pyrimidine group, a pyridazinegroup, a quinoline group, an isoquinoline group, a benzoquinoline group,a quinoxaline group, a quinazoline group, a carbazole group, abenzimidazole group, a benzofuran group, a benzothiophene group, anisobenzothiophene group, a benzoxazole group, an isobenzoxazole group, atriazole group, a tetrazole group, an oxadiazole group, a triazinegroup, a dibenzofuran group, and a dibenzothiophene group.

In one or more embodiments, in Formula 402, i) X₄₀₁ may be nitrogen, andX₄₀₂ may be carbon or ii) X₄₀₁ and X₄₀₂ may each be nitrogen at the sametime.

In one or more embodiments, R₄₀₁ and R₄₀₂ in Formula 402 may eachindependently be selected from

hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, an amidino group, a hydrazino group, a hydrazono group, aC₁-C₂₀ alkyl group, and a C₁-C₂₀ alkoxy group;

a C₁-C₂₀ alkyl group and a C₁-C₂₀ alkoxy group, each substituted with atleast one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, acyano group, a nitro group, an amidino group, a hydrazino group, ahydrazono group, a phenyl group, a naphthyl group, a cyclopentyl group,a cyclohexyl group, an adamantanyl group, a norbornanyl group, and anorbornenyl group;

a cyclopentyl group, a cyclohexyl group, an adamantanyl group, anorbornanyl group, a norbornenyl group, a phenyl group, a biphenylgroup, a terphenyl group, a naphthyl group, a fluorenyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a triazinyl group, a quinolinyl group, an isoquinolinyl group, aquinoxalinyl group, a quinazolinyl group, a carbazolyl group, adibenzofuranyl group, and a dibenzothiophenyl group;

a cyclopentyl group, a cyclohexyl group, an adamantanyl group, anorbornanyl group, a norbornenyl group a phenyl group, a biphenyl group,a terphenyl group, a naphthyl group, a fluorenyl group, a pyridinylgroup, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, atriazinyl group, a quinolinyl group, an isoquinolinyl group, aquinoxalinyl group, a quinazolinyl group, a carbazolyl group, adibenzofuranyl group, and a dibenzothiophenyl group, each substitutedwith at least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxylgroup, a cyano group, a nitro group, an amidino group, a hydrazinogroup, a hydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, acyclopentyl group, a cyclohexyl group, an adamantanyl group, anorbornanyl group, a norbornenyl group, a phenyl group, a biphenylgroup, a terphenyl group, a naphthyl group, a fluorenyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a triazinyl group, a quinolinyl group, an isoquinolinyl group, aquinoxalinyl group, a quinazolinyl group, a carbazolyl group, adibenzofuranyl group, and a dibenzothiophenyl group; and

—Si(Q₄₀₁)(Q₄₀₂)(Q₄₀₃), —N(Q₄₀₁)(Q₄₀₂), —B(Q₄₀₁)(Q₄₀₂), —C(═O)(Q₄₀₁),—S(═O)₂(Q₄₀₁), and —P(═O)(Q₄₀₁)(Q₄₀₂), and

Q₄₀₁ to Q₄₀₃ may each independently be selected from a C₁-C₁₀ alkylgroup, a C₁-C₁₀ alkoxy group, a phenyl group, a biphenyl group, and anaphthyl group.

In one or more embodiments, when xc1 in Formula 401 is two or more, twoA₄₀₁(s) in two or more L₄₀₁(s) may optionally be linked via X₄₀₇, whichis a linking group, or two A₄₀₂(S) in two or more L₄₀₁(s) may optionallybe linked via X₄₀₈, which is a linking group (see Compounds PD1 to PD4and PD7). In one or more embodiments, X₄₀₇ and X₄₀₈ may eachindependently be a single bond, *—O—*′, *—S—*′, *—C(═O)—*′,*—N(Q₄₁₃)-*′, *—C(Q₄₁₃)(Q₄₁₄)-*′ or *—C(Q₄₁₃)=C(Q₄₁₄)-*′ (wherein Q₄₁₃and Q₄₁₄ may each independently be hydrogen, deuterium, a C₁-C₂₀ alkylgroup, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, or a naphthyl group).

L₄₀₂ in Formula 401 may be a monovalent, divalent, or trivalent organicligand. For example, L₄₀₂ in Formula 401 may be selected from halogen,diketone (for example, acetylacetonate), carboxylic acid (for example,picolinate), —C(═O), isonitrile, —CN, and phosphorus (for example,phosphine or phosphite).

In one or more embodiments, the phosphorescent dopant may be, forexample, selected from Compounds PD1 to PD25:

[Fluorescent Dopant in Emission Layer]

The fluorescent dopant may include, for example, an arylamine compoundor a styrylamine compound.

The fluorescent dopant may include, for example, a compound representedby Formula 501 below.

In Formula 501,

Ar₅₀₁ may be a substituted or unsubstituted C₅-C₆₀ carbocyclic group ora substituted or unsubstituted C₁-C₆₀ heterocyclic group,

L₅₀₁ to L₅₀₃ may each independently be selected from a substituted orunsubstituted C₃-C₁₀ cycloalkylene group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkylene group, a substituted or unsubstituted C₃-C₁₀cycloalkenylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenylene group, a substituted or unsubstituted C₆-C₆₀arylene group, a substituted or unsubstituted C₁-C₆₀ heteroarylenegroup, a substituted or unsubstituted divalent non-aromatic condensedpolycyclic group, and a substituted or unsubstituted divalentnon-aromatic condensed heteropolycyclic group,

xd1 to xd3 may each independently be an integer of 0 to 3,

R₅₀₁ and R₅₀₂ may each independently be selected from a substituted orunsubstituted C₃-C₁₀ cycloalkyl group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀cycloalkenyl group, a substituted or unsubstituted C₁-C₀heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀ arylgroup, a substituted or unsubstituted C₆-C₆₀ aryloxy group, asubstituted or unsubstituted C₆-C₆₀ arylthio group, a substituted orunsubstituted C₁-C₆₀ heteroaryl group, a substituted or unsubstitutedmonovalent non-aromatic condensed polycyclic group, and a substituted orunsubstituted monovalent non-aromatic condensed heteropolycyclic group,and

xd4 may be an integer of 1 to 6.

In an embodiment, Ar₅₀₁ in Formula 501 may be selected from:

a naphthalene group, a heptalene group, a fluorene group, aspiro-bifluorene group, a benzofluorene group, a dibenzofluorene group,a phenalene group, a phenanthrene group, an anthracene group, afluoranthene group, a triphenylene group, a pyrene group, a chrysenegroup, a naphthacene group, a picene group, a perylene group, apentaphene group, an indenoanthracene group, and an indenophenanthrenegroup; and

a naphthalene group, a heptalene group, a fluorene group, aspiro-bifluorene group, a benzofluorene group, a dibenzofluorene group,a phenalene group, a phenanthrene group, an anthracene group, afluoranthene group, a triphenylene group, a pyrene group, a chrysenegroup, a naphthacene group, a picene group, a perylene group, apentaphene group, an indenoanthracene group, and an indenophenanthrenegroup, each substituted with at least one selected from deuterium, —F,—Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidinogroup, a hydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, aC₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, a terphenylgroup, and a naphthyl group.

In one or more embodiments, L₅₀₁ to L₅₀₃ in Formula 501 may eachindependently be selected from:

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a fluoranthenylene group, a triphenylenylene group, a pyrenylenegroup, a chrysenylene group, a perylenylene group, a pentaphenylenegroup, a hexacenylene group, a pentacenylene group, a thiophenylenegroup, a furanylene group, a carbazolylene group, an indolylene group,an isoindolylene group, a benzofuranylene group, a benzothiophenylenegroup, a dibenzofuranylene group, a dibenzothiophenylene group, abenzocarbazolylene group, a dibenzocarbazolylene group, adibenzosilolylene group, and a pyridinylene group; and

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a fluoranthenylene group, a triphenylenylene group, a pyrenylenegroup, a chrysenylene group, a perylenylene group, a pentaphenylenegroup, a hexacenylene group, a pentacenylene group, a thiophenylenegroup, a furanylene group, a carbazolylene group, an indolylene group,an isoindolylene group, a benzofuranylene group, a benzothiophenylenegroup, a dibenzofuranylene group, a dibenzothiophenylene group, abenzocarbazolylene group, a dibenzocarbazolylene group, adibenzosilolylene group, and a pyridinylene group, each substituted withat least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxylgroup, a cyano group, a nitro group, an amidino group, a hydrazinogroup, a hydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, aphenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, and a pyridinyl group.

In one or more embodiments, R₅₀₁ and R₅₀₂ in Formula 502 may eachindependently be selected from:

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, and a pyridinyl group; and

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, and a pyridinyl group, each substituted with atleast one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, acyano group, a nitro group, an amidino group, a hydrazino group, ahydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenylgroup, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, and —Si(Q₃₁)(Q₃₂)(Q₃₃), and

Q₃₁ to Q₃₃ may each independently be selected from a C₁-C₁₀ alkyl group,a C₁-C₁₀ alkoxy group, a phenyl group, a biphenyl group, a terphenylgroup, and a naphthyl group.

In one or more embodiments, xd4 in Formula 501 may be 2.

For example, the fluorescent dopant may be selected from Compounds FD1to FD22:

In one or more embodiments, the fluorescent dopant may be selected fromthe following compounds.

[Electron Transport Region in Organic Layer 150]

The electron transport region may have, for example, i) a single-layeredstructure including a single layer including a single material, ii) asingle-layered structure including a single layer including a pluralityof different materials, or iii) a multi-layered structure having aplurality of layers including a plurality of different materials.

The electron transport region may include, for example, at least oneselected from a buffer layer, a hole blocking layer, an electron controllayer, an electron transport layer, and an electron injection layer.

For example, the electron transport region may have an electrontransport layer/electron injection layer structure, a hole blockinglayer/electron transport layer/electron injection layer structure, anelectron control layer/electron transport layer/electron injection layerstructure, or a buffer layer/electron transport layer/electron injectionlayer structure, wherein, for each structure, constituting layers aresequentially stacked from an emission layer. However, embodiments of thestructure of the electron transport region are not limited thereto.

The electron transport region (for example, a buffer layer, a holeblocking layer, an electron control layer, or an electron transportlayer in the electron transport region) may include a metal-freecompound containing at least one π electron-depleted nitrogen-containingring.

The “π electron-depleted nitrogen-containing ring” indicates a C₁-C₆₀heterocyclic group having at least one *—N═*′ moiety as a ring-formingmoiety.

For example, the “π electron-depleted nitrogen-containing ring” may bei) a 5-membered to 7-membered heteromonocyclic group having at least one*—N═*′ moiety, ii) a heteropolycyclic group in which two or more5-membered to 7-membered heteromonocyclic groups each having at leastone *—N═*′ moiety are condensed with each other, or iii) aheteropolycyclic group in which at least one of 5-membered to 7-memberedheteromonocyclic groups, each having at least one *—N═*′ moiety, iscondensed with at least one C₅-C₆₀ carbocyclic group.

Examples of the π electron-depleted nitrogen-containing ring include animidazole, a pyrazole, a thiazole, an isothiazole, an oxazole, anisoxazole, a pyridine, a pyrazine, a pyrimidine, a pyridazine, anindazole, a purine, a quinoline, an isoquinoline, a benzoquinoline, aphthalazine, a naphthyridine, a quinoxaline, a quinazoline, a cinnoline,a phenanthridine, an acridine, a phenanthroline, a phenazine, abenzimidazole, an isobenzothiazole, a benzoxazole, an isobenzoxazole, atriazole, a tetrazole, an oxadiazole, a triazine, thiadiazol, animidazopyridine, an imidazopyrimidine, and an azacarbazole, but are notlimited thereto.

For example, the electron transport region may include, in addition tothe heterocyclic compound represented by Formula 1, a compoundrepresented by Formula 601.

[Ar₆₀₁]_(xc11)-[(L₆₀₁)_(xc1)-R₆₀₁]_(xc21).  <Formula 601>

In Formula 601,

Ar₆₀₁ may be a substituted or unsubstituted C₅-C₆₀ carbocyclic group ora substituted or unsubstituted C₁-C₆₀ heterocyclic group.

xe11 may be 1, 2, or 3.

L₆₀₁ may be selected from a substituted or unsubstituted C₃-C₁₀cycloalkylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkylene group, a substituted or unsubstituted C₃-C₁₀cycloalkenylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenylene group, a substituted or unsubstituted C₆-C₆₀arylene group, a substituted or unsubstituted C₁-C₆₀ heteroarylenegroup, a substituted or unsubstituted divalent non-aromatic condensedpolycyclic group, and a substituted or unsubstituted divalentnon-aromatic condensed heteropolycyclic group,

xe1 may be an integer of 0 to 5,

R₆₀₁ may be selected from a substituted or unsubstituted C₃-C₁₀cycloalkyl group, a substituted or unsubstituted C₁-C₁₀ heterocycloalkylgroup, a substituted or unsubstituted C₃-C₁₀ cycloalkenyl group, asubstituted or unsubstituted C₁-C₁₀ heterocycloalkenyl group, asubstituted or unsubstituted C₆-C₆₀ aryl group, a substituted orunsubstituted C₆-C₆₀ aryloxy group, a substituted or unsubstitutedC₆-C₆₀ arylthio group, a substituted or unsubstituted C₁-C₆₀ heteroarylgroup, a substituted or unsubstituted monovalent non-aromatic condensedpolycyclic group, a substituted or unsubstituted monovalent non-aromaticcondensed heteropolycyclic group, —Si(Q₆₀₁)(Q₆₀₂)(Q₆₀₃), —C(═O)(Q₆₀₁),—S(═O)₂(Q₆₀₁), and —P(═O)(Q₆₀₁)(Q₆₀₂),

Q₆₀₁ to Q₆₀₃ may each independently be a C₁-C₁₀ alkyl group, a C₁-C₁₀alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, or anaphthyl group, and

xe21 may be an integer from 1 to 5.

In an embodiment, at least one selected from xe11 Ar₆₀₁(s) and xe21R₆₀₁(s) may include the π electron-depleted nitrogen-containing ring.

In an embodiment, in Formula 601, ring Ar₆₀₁ may be selected from:

a benzene group, a naphthalene group, a fluorene group, aspiro-bifluorene group, a benzofluorene group, a dibenzofluorene group,a phenalene group, a phenanthrene group, an anthracene group, afluoranthene group, a triphenylene group, a pyrene group, a chrysenegroup, a naphthacene group, a picene group, a perylene group, apentaphene group, an indenoanthracene group, a dibenzofuran group, adibenzothiophene group, a carbazole group, an imidazole group, apyrazole group, a thiazole group, an isothiazole group, an oxazolegroup, an isoxazole group, a pyridine group, a pyrazine group, apyrimidine group, a pyridazine group, an indazole group, a purine group,a quinoline group, an isoquinoline group, a benzoquinoline group, aphthalazine group, a naphthyridine group, a quinoxaline group, aquinazoline group, a cinnoline group, a phenanthridine group, anacridine group, a phenanthroline group, a phenazine group, abenzimidazole group, an iso-benzothiazole group, a benzoxazole group, anisobenzoxazole group, a triazole group, a tetrazole group, an oxadiazolegroup, a triazine group, a thiadiazol group, an imidazopyridine group,an imidazopyrimidine group, and an azacarbazole group; and

a benzene group, a naphthalene group, a fluorene group, aspiro-bifluorene group, a benzofluorene group, a dibenzofluorene group,a phenalene group, a phenanthrene group, an anthracene group, afluoranthene group, a triphenylene group, a pyrene group, a chrysenegroup, a naphthacene group, a picene group, a perylene group, apentaphene group, an indenoanthracene group, a dibenzofuran group, adibenzothiophene group, a carbazole group, an imidazole group, apyrazole group, a thiazole group, an isothiazole group, an oxazolegroup, an isoxazole group, a pyridine group, a pyrazine group, apyrimidine group, a pyridazine group, an indazole group, a purine group,a quinoline group, an isoquinoline group, a benzoquinoline group, aphthalazine group, a naphthyridine group, a quinoxaline group, aquinazoline group, a cinnoline group, a phenanthridine group, anacridine group, a phenanthroline group, a phenazine group, abenzimidazole group, an iso-benzothiazole group, a benzoxazole group, anisobenzoxazole group, a triazole group, a tetrazole group, an oxadiazolegroup, a triazine group, a thiadiazol group, an imidazopyridine group,an imidazopyrimidine group, and an azacarbazole group, each substitutedwith at least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxylgroup, a cyano group, a nitro group, an amidino group, a hydrazinogroup, a hydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, aphenyl group, a biphenyl group, a terphenyl group, a naphthyl group,—Si(Q₃₁)(Q₃₂)(Q₃₃), —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), and

Q₃₁ to Q₃₃ may each independently be selected from a C₁-C₁₀ alkyl group,a C₁-C₁₀ alkoxy group, a phenyl group, a biphenyl group, a terphenylgroup, and a naphthyl group.

When xe11 in Formula 601 is two or more, two or more Ar601(s) may belinked via a single bond.

In one or more embodiments, Ar₆₀₁ in Formula 601 may be an anthracenegroup.

In one or more embodiments, a compound represented by Formula 601 may berepresented by Formula 601-1:

In Formula 601-1,

X₆₁₄ may be N or C(R₆₁₄), X₆₁₅ may be N or C(R₆₁₅), and X₆₁₆ may be N orC(R₆₁₆), wherein at least one selected from X₆₁₄ to X₆₁₆ may be N,

L₆₁₁ to L₆₁₃ may each independently be the same as defined in connectionwith L₆₀₁,

xe611 to xe613 may each independently be the same as defined inconnection with xe1,

R₆₁₁ to R₆₁₃ may each independently be the same as defined in connectionwith R₆₀₁, and

R₆₁₄ to R₆₁₆ may each independently be selected from hydrogen,deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, and a naphthyl group.

In an embodiment, L₆₀₁ and L₆₁₁ to L₆₁₃ in Formulae 601 and 601-1 mayeach independently be selected from:

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a fluoranthenylene group, a triphenylenylene group, a pyrenylenegroup, a chrysenylene group, a perylenylene group, a pentaphenylenegroup, a hexacenylene group, a pentacenylene group, a thiophenylenegroup, a furanylene group, a carbazolylene group, an indolylene group,an isoindolylene group, a benzofuranylene group, a benzothiophenylenegroup, a dibenzofuranylene group, a dibenzothiophenylene group, abenzocarbazolylene group, a dibenzocarbazolylene group, adibenzosilolylene group, a pyridinylene group, an imidazolylene group, apyrazolylene group, a thiazolylene group, an isothiazolylene group, anoxazolylene group, an isoxazolylene group, a thiadiazolylene group, anoxadiazolylene group, a pyrazinylene group, a pyrimidinylene group, apyridazinylene group, a triazinylene group, a quinolinylene group, anisoquinolinylene group, a benzoquinolinylene group, a phthalazinylenegroup, a naphthyridinylene group, a quinoxalinylene group, aquinazolinylene group, a cinnolinylene group, a phenanthridinylenegroup, an acridinylene group, a phenanthrolinylene group, aphenazinylene group, a benzimidazolylene group, an isobenzothiazolylenegroup, a benzoxazolylene group, an isobenzoxazolylene group, atriazolylene group, a tetrazolylene group, an imidazopyridinylene group,an imidazopyrimidinylene group, and an azacarbazolylene group; and

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a fluoranthenylene group, a triphenylenylene group, a pyrenylenegroup, a chrysenylene group, a perylenylene group, a pentaphenylenegroup, a hexacenylene group, a pentacenylene group, a thiophenylenegroup, a furanylene group, a carbazolylene group, an indolylene group,an isoindolylene group, a benzofuranylene group, a benzothiophenylenegroup, a dibenzofuranylene group, a dibenzothiophenylene group, abenzocarbazolylene group, a dibenzocarbazolylene group, adibenzosilolylene group, a pyridinylene group, an imidazolylene group, apyrazolylene group, a thiazolylene group, an isothiazolylene group, anoxazolylene group, an isoxazolylene group, a thiadiazolylene group, anoxadiazolylene group, a pyrazinylene group, a pyrimidinylene group, apyridazinylene group, a triazinylene group, a quinolinylene group, anisoquinolinylene group, a benzoquinolinylene group, a phthalazinylenegroup, a naphthyridinylene group, a quinoxalinylene group, aquinazolinylene group, a cinnolinylene group, a phenanthridinylenegroup, an acridinylene group, a phenanthrolinylene group, aphenazinylene group, a benzimidazolylene group, an isobenzothiazolylenegroup, a benzoxazolylene group, an isobenzoxazolylene group, atriazolylene group, a tetrazolylene group, an imidazopyridinylene group,an imidazopyrimidinylene group, and an azacarbazolylene group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, anaphthyl group, a fluorenyl group, a spiro-bifluorenyl group, abenzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group,an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a perylenyl group, a pentaphenylgroup, a hexacenyl group, a pentacenyl group, a thiophenyl group, afuranyl group, a carbazolyl group, an indolyl group, an isoindolylgroup, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranylgroup, a dibenzothiophenyl group, a benzocarbazolyl group, adibenzocarbazolyl group, a dibenzosilolyl group, a pyridinyl group, animidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolylgroup, an oxazolyl group, an isoxazolyl group, a thiadiazolyl group, anoxadiazolyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a triazinyl group, a quinolinyl group, an isoquinolinyl group, abenzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, aquinoxalinyl group, a quinazolinyl group, a cinnolinyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, aphenazinyl group, a benzimidazolyl group, an isobenzothiazolyl group, abenzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, atetrazolyl group, an imidazopyridinyl group, an imidazopyrimidinylgroup, and an azacarbazolyl group.

In one or more embodiments, xe1 and xe611 to xe613 in Formulae 601 and601-1 may each independently be 0, 1, or 2.

In one or more embodiments, R₆₀₁ and R₆₁₁ to R₆₁₃ in Formula 601 and601-1 may each independently be selected from:

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, an imidazolyl group, apyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolylgroup, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group,a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinylgroup, a quinolinyl group, an isoquinolinyl group, a benzoquinolinylgroup, a phthalazinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a cinnolinyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolylgroup, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group,an imidazopyridinyl group, an imidazopyrimidinyl group, and anazacarbazolyl group;

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, an imidazolyl group, apyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolylgroup, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group,a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinylgroup, a quinolinyl group, an isoquinolinyl group, a benzoquinolinylgroup, a phthalazinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a cinnolinyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolylgroup, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group,an imidazopyridinyl group, an imidazopyrimidinyl group, and anazacarbazolyl group, each substituted with at least one selected fromdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, a naphthyl group, a fluorenyl group, aspiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenylgroup, a phenanthrenyl group, an anthracenyl group, a fluoranthenylgroup, a triphenylenyl group, a pyrenyl group, a chrysenyl group, aperylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a thiophenyl group, a furanyl group, a carbazolyl group, anindolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, an imidazolyl group, apyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolylgroup, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group,a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinylgroup, a quinolinyl group, an isoquinolinyl group, a benzoquinolinylgroup, a phthalazinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a cinnolinyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolylgroup, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group,an imidazopyridinyl group, an imidazopyrimidinyl group, and anazacarbazolyl group; and

—S(═O)₂(Q₆₀₁), and —P(═O)(Q₆₀₁)(Q₆₀₂), and

descriptions of Q₆₀₁ and Q₆₀₂ are the same as defined above.

The electron transport region may include, for example, at least onecompound selected from Compounds ET1 to ET36:

In one or more embodiments, the electron transport region may include,for example, at least one selected from2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP),4,7-diphenyl-1,10-phenanthroline (Bphen), Alq₃, BAlq,3-(biphenyl-4-yl)-5-(4-tert-butylphenyl)-4-phenyl-4H-1,2,4-triazole(TAZ), and NTAZ.

A thickness of the buffer layer, the hole blocking layer, or theelectron control layer may be in a range of, for example, about 20 Å toabout 1,000 Å, for example, about 30 Å to about 300 Å. When thethicknesses of the buffer layer, the hole blocking layer, and theelectron control layer are within these ranges, the electron blockinglayer may have excellent electron blocking characteristics or electroncontrol characteristics without a substantial increase in drivingvoltage.

A thickness of the electron transport layer may be, for example, in arange of about 100 Å to about 1,000 Å, for example, about 150 Å to about500 Å. When the thickness of the electron transport layer is within therange described above, the electron transport layer may havesatisfactory electron transport characteristics without a substantialincrease in driving voltage.

The electron transport region (for example, the electron transport layerin the electron transport region) may further include, in addition tothe materials described above, a metal-containing material.

The metal-containing material may include, for example, at least one ofan alkali metal complex and an alkaline earth-metal complex. The alkalimetal complex may include a metal ion selected from a Li ion, a Na ion,a K ion, a Rb ion, and a Cs ion, and the alkaline earth-metal complexmay include a metal ion selected from a Be ion, a Mg ion, a Ca ion, a Srion, and a Ba ion. A ligand coordinated with the metal ion of the alkalimetal complex or the alkaline earth-metal complex may be selected from ahydroxy quinoline, a hydroxy isoquinoline, a hydroxy benzoquinoline, ahydroxy acridine, a hydroxy phenanthridine, a hydroxy phenyloxazole, ahydroxy phenylthiazole, a hydroxy diphenyloxadiazole, a hydroxy diphenylthiadiazol, a hydroxy phenylpyridine, a hydroxy phenylbenzimidazole, ahydroxy phenylbenzothiazole, a bipyridine, a phenanthroline, and acyclopentadiene.

For example, the metal-containing material may include a Li complex. TheLi complex may include, for example, Compound ET-DI (lithium quinolate,LiQ) or ET-D2.

The electron transport region may include an electron injection layerthat facilitates injection of electrons from the second electrode 190.The electron injection layer may directly contact the second electrode190.

The electron injection layer may have, for example, i) a single-layeredstructure including a single layer including a single material, ii) asingle-layered structure including a single layer including a pluralityof different materials, or iii) a multi-layered structure having aplurality of layers including a plurality of different materials.

The electron injection layer may include, for example, an alkali metal,an alkaline earth metal, a rare earth metal, an alkali metal compound,an alkaline earth-metal compound, a rare earth metal compound, an alkalimetal complex, an alkaline earth-metal complex, a rare earth metalcomplex, or a combination thereof.

The alkali metal may be selected from Li, Na, K, Rb, and Cs. In anembodiment, the alkali metal may be Li, Na, or Cs. In one or moreembodiments, the alkali metal may be Li or Cs.

The alkaline earth metal may be selected from Mg, Ca, Sr, and Ba.

The rare earth metal may be selected from Sc, Y, Ce, Tb, Yb, and Gd.

The alkali metal compound, the alkaline earth-metal compound, and therare earth metal compound may be selected from oxides and halides (forexample, fluorides, chlorides, bromides, or iodides) of the alkalimetal, the alkaline earth-metal, and the rare earth metal.

The alkali metal compound may be selected from alkali metal oxides, suchas Li₂O, Cs₂O, or K₂O, and alkali metal halides, such as LiF, NaF, CsF,KF, LiI, NaI, CsI, or KI. In an embodiment, the alkali metal compoundmay be selected from LiF, Li₂O, NaF, LiI, NaI, CsI, and KI.

The alkaline earth-metal compound may be selected from alkalineearth-metal oxides, such as BaO, SrO, CaO, Ba_(x)Sr_(1-x)O (0<x<1), andBa_(x)Ca_(1-x)O (0<x<1). In an embodiment, the alkaline earth-metalcompound may be selected from BaO, SrO, and CaO.

The rare earth metal compound may be selected from YbF₃, ScF₃, ScO₃,Y₂O₃, Ce₂O₃, GdF₃, and TbF₃. In an embodiment, the rare earth metalcompound may be selected from YbF₃, ScF₃, TbF₃, YbI₃, ScI₃, and TbI₃.

The alkali metal complex, the alkaline earth-metal complex, and the rareearth metal complex may include an ion of alkali metal, alkalineearth-metal, and rare earth metal as described above, and a ligandcoordinated with a metal ion of the alkali metal complex, the alkalineearth-metal complex, or the rare earth metal complex may be selectedfrom hydroxy quinoline, hydroxy isoquinoline, hydroxy benzoquinoline,hydroxy acridine, hydroxy phenanthridine, hydroxy phenyloxazole, hydroxyphenylthiazole, hydroxy diphenyloxadiazole, hydroxy diphenylthiadiazol,hydroxy phenylpyridine, hydroxy phenylbenzimidazole, hydroxyphenylbenzothiazole, bipyridine, phenanthroline, and cyclopentadiene.

The electron injection layer may include an alkali metal, an alkalineearth metal, a rare earth metal, an alkali metal compound, an alkalineearth-metal compound, a rare earth metal compound, an alkali metalcomplex, an alkaline earth-metal complex, a rare earth metal complex, ora combination thereof, as described above. In one or more embodiments,the electron injection layer may further include an organic material.When the electron injection layer further includes an organic material,an alkali metal, an alkaline earth metal, a rare earth metal, an alkalimetal compound, an alkaline earth-metal compound, a rare earth metalcompound, an alkali metal complex, an alkaline earth-metal complex, arare earth metal complex, or a combination thereof may be homogeneouslyor non-homogeneously dispersed in a matrix including the organicmaterial.

A thickness of the electron injection layer may be in a range of, forexample, about 1 Å to about 100 Å, for example, about 3 Å to about 90 Å.When the thickness of the electron injection layer is within the rangedescribed above, the electron injection layer may have satisfactoryelectron injection characteristics without a substantial increase indriving voltage.

[Second Electrode 190]

The second electrode 190 may be disposed on the organic layer 150 havingsuch a structure. The second electrode 190 may be a cathode which is anelectron injection electrode, and in this regard, a material for formingthe second electrode 190 may be selected from, for example, a metal, analloy, an electrically conductive compound, and a combination thereof,which may have a relatively low work function.

The second electrode 190 may include, for example, at least one selectedfrom Li, Ag, Mg, Al, Al—Li, Ca, Mg—In, Mg—Ag, ITO, and IZO. The secondelectrode 190 may be, for example, a transmissive electrode, asemi-transmissive electrode, or a reflective electrode.

The second electrode 190 may have, for example, a single-layeredstructure, or a multi-layered structure including two or more layers.

[Description of FIGS. 2 to 4]

An organic light-emitting device 20 of FIG. 2 includes a first cappinglayer 210, a first electrode 110, an organic layer 150, and a secondelectrode 190 which are sequentially stacked in this stated order, anorganic light-emitting device 30 of FIG. 3 includes a first electrode110, an organic layer 150, a second electrode 190, and a second cappinglayer 220 which are sequentially stacked in this stated order, and anorganic light-emitting device 40 of FIG. 4 includes a first cappinglayer 210, a first electrode 110, an organic layer 150, a secondelectrode 190, and a second capping layer 220 which are sequentiallystacked in this stated order.

Regarding FIGS. 2 to 4, the first electrode 110, the organic layer 150,and the second electrode 190 may be understood by referring to thedescription presented in connection with FIG. 1.

In the organic layer 150 of each of the organic light-emitting devices20 and 40, light generated in an emission layer may pass through thefirst electrode 110, which may be, for example, a semi-transmissiveelectrode or a transmissive electrode, and the first capping layer 210toward the outside, and in the organic layer 150 of each of the organiclight-emitting devices 30 and 40, light generated in an emission layermay pass through the second electrode 190, which may be, for example, asemi-transmissive electrode or a transmissive electrode, and the secondcapping layer 220 toward the outside.

The first capping layer 210 and the second capping layer 220 mayincrease external luminescent efficiency according to the principle ofconstructive interference.

The first capping layer 210 and the second capping layer 220 may eachindependently be, for example, an organic capping layer including anorganic material, an inorganic capping layer including an inorganicmaterial, or a composite capping layer including an organic material andan inorganic material.

At least one selected from the first capping layer 210 and the secondcapping layer 220 may each independently include, for example, at leastone material selected from carbocyclic compounds, heterocycliccompounds, amine-based compounds, porphrine derivatives, phthalocyaninederivatives, a naphthalocyanine derivatives, alkali metal complexes, andalkaline earth-based complexes. The carbocyclic compound, theheterocyclic compound, and the amine-based compound may be optionallysubstituted with a substituent containing at least one element selectedfrom O, N, S, Se, Si, F, Cl, Br, and I. In an embodiment, at least oneselected from the first capping layer 210 and the second capping layer220 may each independently include an amine-based compound.

In an embodiment, at least one selected from the first capping layer 210and the second capping layer 220 may each independently include, forexample, the compound represented by Formula 201 or the compoundrepresented by Formula 202.

In one or more embodiments, at least one selected from the first cappinglayer 210 and the second capping layer 220 may each independentlyinclude, for example, a compound selected from Compounds HT28 to HT33and Compounds CP1 to CP5.

Layers constituting the hole transport region, an emission layer, andlayers constituting the electron transport region may be formed in acertain region by using one or more suitable methods selected from, forexample, vacuum deposition, spin coating, casting, Langmuir-Blodgett(LB) deposition, ink-jet printing, laser-printing, and laser-inducedthermal imaging.

When layers constituting the hole transport region, an emission layer,and layers constituting the electron transport region are formed byvacuum deposition, the vacuum deposition may be performed, for example,at a deposition temperature of about 100° C. to about 500° C., at avacuum degree of about 10⁻⁸ torr to about 10⁻³ torr, and at a depositionrate of about 0.01 Å/sec to about 100 Å/sec by taking into account amaterial to be included in a layer to be formed and the structure of alayer to be formed.

When layers constituting the hole transport region, an emission layer,and layers constituting the electron transport region are formed by spincoating, the spin coating may be performed, for example, at a coatingspeed of about 2000 rpm to about 5000 rpm and at a heat treatmenttemperature of about 80° C. to 200° C. by taking into account a materialto be included in a layer to be formed and the structure of a layer tobe formed.

[General Definition of Substituents]

The term “C₁-C₆₀ alkyl group” as used herein refers to a linear orbranched saturated aliphatic hydrocarbon monovalent group having 1 to 60carbon atoms, and examples thereof include a methyl group, an ethylgroup, a propyl group, an isobutyl group, a sec-butyl group, atert-butyl group, a pentyl group, an iso-amyl group, and a hexyl group.The term “C₁-C₆₀ alkylene group” as used herein refers to a divalentgroup having the same structure as the C₁-C₆₀ alkyl group.

The term “C₂-C₆₀ alkenyl group” as used herein refers to a hydrocarbongroup having at least one carbon-carbon double bond in the middle or atthe terminus of the C₂-C₆₀ alkyl group, and examples thereof include anethenyl group, a propenyl group, and a butenyl group. The term “C₂-C₆₀alkenylene group” as used herein refers to a divalent group having thesame structure as the C₂-C₆₀ alkenyl group.

The term “C₂-C₆₀ alkynyl group” as used herein refers to a hydrocarbongroup having at least one carbon-carbon triple bond in the middle or atthe terminus of the C₂-C₆₀ alkyl group, and examples thereof include anethynyl group and a propynyl group. The term “C₂-C₆₀ alkynylene group”as used herein refers to a divalent group having the same structure asthe C₂-C₆₀ alkynyl group.

The term “C₁-C₆₀ alkoxy group” as used herein refers to a monovalentgroup represented by —OA₁₀₁ (wherein A₁₀₁ is the C₁-C₆₀ alkyl group),and examples thereof include a methoxy group, an ethoxy group, and anisopropyloxy group.

The term “C₃-C₁₀ cycloalkyl group” as used herein refers to a monovalentsaturated hydrocarbon monocyclic group having 3 to 10 carbon atoms, andexamples thereof include a cyclopropyl group, a cyclobutyl group, acyclopentyl group, a cyclohexyl group, and a cycloheptyl group. The term“C₃-C₁₀ cycloalkylene group” as used herein refers to a divalent grouphaving the same structure as the C₃-C₁₀ cycloalkyl group.

The term “C₁-C₁₀ heterocycloalkyl group” as used herein refers to amonovalent monocyclic group having at least one heteroatom selected fromN, O, Si, P, and S as a ring-forming atom and 1 to 10 carbon atoms, andexamples thereof include a 1,2,3,4-oxatriazolidinyl group, atetrahydrofuranyl group, and a tetrahydrothiophenyl group. The term“C₁-C₁₀ heterocycloalkylene group” used herein refers to a divalentgroup having the same structure as the C₁-C₁₀ heterocycloalkyl group.

The term “C₃-C₁₀ cycloalkenyl group” as used herein refers to amonovalent monocyclic group that has 3 to 10 carbon atoms and at leastone carbon-carbon double bond in the ring thereof and no aromaticity,and examples thereof include a cyclopentenyl group, a cyclohexenylgroup, and a cycloheptenyl group. The term “C₃-C₁₀ cycloalkenylenegroup” as used herein refers to a divalent group having the samestructure as the C₃-C₁₀ cycloalkenyl group.

The term “C₁-C₁₀ heterocycloalkenyl group” as used herein refers to amonovalent monocyclic group that has at least one heteroatom selectedfrom N, O, Si, P, and S as a ring-forming atom, 1 to 10 carbon atoms,and at least one carbon-carbon double bond in its ring. Examples of theC₁-C₁₀ heterocycloalkenyl group include a4,5-dihydro-1,2,3,4-oxatriazolyl group, a 2,3-dihydrofuranyl group, anda 2,3-dihydrothiophenyl group. The term “C₁-C₁₀ heterocycloalkenylenegroup” as used herein refers to a divalent group having the samestructure as the C₁-C₁₀ heterocycloalkenyl group.

The term “C₆-C₆₀ aryl group” as used herein refers to a monovalent grouphaving a carbocyclic aromatic system having 6 to 60 carbon atoms, and aC₆-C₆₀ arylene group used herein refers to a divalent group having acarbocyclic aromatic system having 6 to 60 carbon atoms. Examples of theC₆-C₆₀ aryl group are a phenyl group, a naphthyl group, an anthracenylgroup, a phenanthrenyl group, a pyrenyl group, and a chrysenyl group.When the C₆-C₆₀ aryl group and the C₆-C₆₀ arylene group each include twoor more rings, the rings may be fused to each other.

The term “C₁-C₆₀ heteroaryl group” as used herein refers to a monovalentgroup having a heterocyclic aromatic system that has at least oneheteroatom selected from N, O, Si, P, and S as a ring-forming atom, inaddition to 1 to 60 carbon atoms. The term “C₁-C₆₀ heteroarylene group”as used herein refers to a divalent group having a heterocyclic aromaticsystem that has at least one heteroatom selected from N, O, Si, P, and Sas a ring-forming atom, in addition to 1 to 60 carbon atoms. Examples ofthe C₁-C₆₀ heteroaryl group are a pyridinyl group, a pyrimidinyl group,a pyrazinyl group, a pyridazinyl group, a triazinyl group, a quinolinylgroup, and an isoquinolinyl group. When the C₁-C₆₀ heteroaryl group andthe C₁-C₆₀ heteroarylene group each include two or more rings, the ringsmay be fused to each other.

The term “C₆-C₆₀ aryloxy group” as used herein indicates —OA₁₀₂ (whereinA₁₀₂ is the C₆-C₆₀ aryl group), and the term “C₆-C₆₀ arylthio group” asused herein indicates —SA₁₀₃ (wherein A₁₀₃ is the C₆-C₆₀ aryl group).

The term “monovalent non-aromatic condensed polycyclic group” as usedherein refers to a monovalent group that has two or more rings condensedand only carbon atoms (e.g., 8 to 60 carbon atoms) as ring-formingatoms, wherein the entire molecular structure is non-aromatic. Examplesof the monovalent non-aromatic condensed polycyclic group may include afluorenyl group. The term “divalent non-aromatic condensed polycyclicgroup” as used herein refers to a divalent group having the samestructure as the monovalent non-aromatic condensed polycyclic group.

The term “monovalent non-aromatic condensed heteropolycyclic group” asused herein refers to a monovalent group that has two or more ringscondensed, at least one heteroatom selected from N, O, Si, P, and S, inaddition to carbon atoms (e.g., 1 to 60 carbon atoms), as ring-formingatoms, wherein the entire molecular structure is non-aromatic. Examplesof the monovalent non-aromatic condensed heteropolycyclic group mayinclude a carbazolyl group. The term “divalent non-aromatic condensedheteropolycyclic group” as used herein refers to a divalent group havingthe same structure as the monovalent non-aromatic condensedheteropolycyclic group.

The term “C₅-C₆₀ carbocyclic group” as used herein refers to amonocyclic or polycyclic group having 5 to 60 carbon atoms in which aring-forming atom is a carbon atom only. The C₅-C₆₀ carbocyclic groupmay be an aromatic carbocyclic group or a non-aromatic carbocyclicgroup. The C₅-C₆₀ carbocyclic group may be a ring, such as a benzenegroup, a monovalent group, such as a phenyl group, or a divalent group,such as a phenylene group. In one or more embodiments, depending on thenumber of substituents connected to the C₅-C₆₀ carbocyclic group, theC₅-C₆₀ carbocyclic group may be a trivalent group or a quadrivalentgroup.

The term “C₁-C₆₀ heterocyclic group” as used herein refers to a grouphaving the same structure as the C₅-C₆₀ carbocyclic group, except thatas a ring-forming atom, at least one heteroatom selected from N, O, Si,P, and S is used in addition to carbon (the number of carbon atoms maybe in a range of 1 to 60).

In the present specification, at least one substituent of thesubstituted C₅-C₆₀ carbocyclic group, the substituted C₁-C₆₀heterocyclic group, the substituted C₃-C₁₀ cycloalkylene group, thesubstituted C₁-C₁₀ heterocycloalkylene group, the substituted C₃-C₁₀cycloalkenylene group, the substituted C₁-C₁₀ heterocycloalkenylenegroup, the substituted C₆-C₆₀ arylene group, the substituted C₁-C₆₀heteroarylene group, the substituted divalent non-aromatic condensedpolycyclic group, the substituted divalent non-aromatic condensedheteropolycyclic group, the substituted C₁-C₆₀ alkyl group, thesubstituted C₂-C₆₀ alkenyl group, the substituted C₂-C₆₀ alkynyl group,the substituted C₁-C₆₀ alkoxy group, the substituted C₃-C₁₀ cycloalkylgroup, the substituted C₁-C₁₀ heterocycloalkyl group, the substitutedC₃-C₆₀ cycloalkenyl group, the substituted C₁-C₁₀ heterocycloalkenylgroup, the substituted C₆-C₆₀ aryl group, the substituted C₆-C₆₀ aryloxygroup, the substituted C₆-C₆₀ arylthio group, the substituted C₁-C₆₀heteroaryl group, the substituted monovalent non-aromatic condensedpolycyclic group, and the substituted monovalent non-aromatic condensedheteropolycyclic group may be selected from:

deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₆₀alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, and aC₁-C₆₀ alkoxy group;

a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group,and a C₁-C₆₀ alkoxy group, each substituted with at least one selectedfrom deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, anitro group, an amidino group, a hydrazino group, a hydrazono group, aC₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,a monovalent non-aromatic condensed heteropolycyclic group,—Si(Q₁₁)(Q₁₂)(Q₁₃), —N(Q₁₁)(Q₁₂), —B(Q₁₁)(Q₁₂), —C(═O)(Q₁₁),—S(═O)₂(Q₁₁), and —P(═O)(Q₁₁)(Q₁₂),

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group;

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenylgroup, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₅₀ aryl group, a C₆-C₆₀aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, amonovalent non-aromatic condensed polycyclic group, a monovalentnon-aromatic condensed heteropolycyclic group, —Si(Q₂₁)(Q₂₂)(Q₂₃),—N(Q₂₁)(Q₂₂), —B(Q₂₁)(Q₂₂), —C(═O)(Q₂₁), —S(═O)₂(Q₂₁), and—P(═O)(Q₂₁)(Q₂₂); and

—Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁),—S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), and

Q₁₁ to Q₁₃, Q₂₁ to Q₂₃, and Q₃₁ to Q₃₃ may each independently beselected from hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, acyano group, a nitro group, an amidino group, a hydrazino group, ahydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, aC₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₁-C₆₀ heteroarylgroup, a monovalent non-aromatic condensed polycyclic group, amonovalent non-aromatic condensed heteropolycyclic group, a biphenylgroup, and a terphenyl group.

The term “Ph” as used herein refers to a phenyl group, the term “Me” asused herein refers to a methyl group, the term “Et” as used hereinrefers to an ethyl group, the term “ter-Bu” or “But” as used hereinrefers to a tert-butyl group, and the term “OMe” as used herein refersto a methoxy group.

The term “biphenyl group” as used herein refers to “a phenyl groupsubstituted with a phenyl group.” In other words, the term “biphenylgroup” is a substituted phenyl group having a C₆-C₆₀ aryl group as asubstituent.

The term “terphenyl group” as used herein refers to “a phenyl groupsubstituted with a biphenyl group.” In other words, the “terphenylgroup” is a phenyl group having, as a substituent, a C₆-C₆₀ aryl groupsubstituted with a C₆-C₆₀ aryl group.

The symbols * and *′ as used herein unless defined otherwise, each referto a binding site to a neighboring atom in a corresponding formula.

Hereinafter, a compound according to embodiments and an organiclight-emitting device according to embodiments will be described indetail with reference to Synthesis Examples and Examples. The wording “Bwas used instead of A” used in describing Synthesis Examples refers tothat an identical molar equivalent of B was used in place of A.

The following Examples and Comparative Examples are provided in order tohighlight characteristics of one or more embodiments, but it will beunderstood that the Examples and Comparative Examples are not to beconstrued as limiting the scope of the embodiments, nor are theComparative Examples to be construed as being outside the scope of theembodiments. Further, it will be understood that the embodiments are notlimited to the particular details described in the Examples andComparative Examples.

EXAMPLES Synthesis Example 1: Synthesis of Compound 13

Synthesis of Intermediate I-1

1.99 g (10 mmol) of 2,3-dichloroquinoxaline, 2.27 g (12 mmol) of4-bromobenzene-1,2-diol, and 4.15 g (30 mmol) of potassium carbonatewere dissolved in 100 ml of DMF, and the mixed solution was stirred atroom temperature for 24 hours. Distilled water was added to the reactionsolution, and an extraction process was performed thereon three timesusing 60 ml of ethyl acetate. An organic layer collected therefrom wasdried using magnesium sulfate (MgSO₄), and then, the residual obtainedby evaporating a solvent therefrom was separation-purified by gelchromatography to obtain 2.68 g (yield: 85%) of Intermediate I-1. Theobtained compound was confirmed by LC-MS.

C₁₄H₇BrN₂O₂: M⁺ 313.97

Synthesis of Compound 13

3.15 g (10 mmol) of Intermediate I-1, 4.73 g (11 mmol) of4,4,5,5-tetramethyl-2-(10-(naphthalen-1-yl)anthracen-9-yl)-1,3,2-dioxaborolane,0.57 g (5 mol %) of Pd(PPh₃)₄, 4.15 g (3 equiv) of K₂CO₃ were dissolvedin 100 ml of a solution containing THF and H₂O at a volume ratio of 2:1,and then, the mixed solution was stirred at a temperature of 80° C. for24 hours. After the reaction solution was cooled to room temperature, anextraction process was performed thereon three times using 60 ml ofethyl acetate. An organic layer collected therefrom was dried usingMgSO₄, and then, the residual obtained by evaporating a solventtherefrom was separation-purified by gel chromatography to obtain 4.15 g(yield: 77%) of Compound 13. The obtained compound was confirmed byLC-MS.

C₃₈H₂₂N₂O₂: M⁺ 538.17

Synthesis Example 2: Synthesis of Compound 15

3.08 g (yield: 63%) of Compound 15 was synthesized in the same manner asin Synthesis of Compound 13, except that4-(10-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)anthracen-9-yl)pyridinewas used instead of4,4,5,5-tetramethyl-2-(10-(naphthalen-1-yl)anthracen-9-yl)-1,3,2-dioxaborolane.The obtained compound was identified by MS/FAB and ¹H NMR.

C₃₃H₁₉N₃O₂: M⁺ 489.15

Synthesis Example 3: Synthesis of Compound 16

3.70 g (yield: 72%) of Compound 16 was synthesized in the same manner asin the Synthesis of Compound 13, except that4-(10-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)anthracen-9-yl)benzonitrilewas used instead of4,4,5,5-tetramethyl-2-(10-(naphthalen-1-yl)anthracen-9-yl)-1,3,2-dioxaborolane.The obtained compound was identified by MS/FAB and ¹H NMR.

C₃₅H₁₉N₃O₂: M⁺ 513.15

Synthesis Example 4: Synthesis of Compound 20

3.92 g (yield: 61%) of Compound 20 was synthesized in the same manner asin the Synthesis of Compound 13, except that3,3′-(5-(10-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)anthracen-9-yl)-1,3-phenylene)dipyridinewas used instead of4,4,5,5-tetramethyl-2-(10-(naphthalen-1-yl)anthracen-9-yl)-1,3,2-dioxaborolane.The obtained compound was identified by MS/FAB and ¹H NMR.

C₄₄H₂₆N₄O₂: M⁺ 643.20

Synthesis Example 5: Synthesis of Compound 21

4.44 g (yield: 69%) of Compound 21 was synthesized in the same manner asin the Synthesis of Compound 13, except that2,4-diphenyl-6-(10-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)anthracen-9-yl)-1,3,5-triazinewas used instead of4,4,5,5-tetramethyl-2-(10-(naphthalen-1-yl)anthracen-9-yl)-1,3,2-dioxaborolane.The obtained compound was identified by MS/FAB and ¹H NMR.

C₄₃H₂₅N₅O₂: M⁺ 643.20

Synthesis Example 6: Synthesis of Compound 27

4.47 g (yield: 71%) of Compound 27 was synthesized in the same manner asin the Synthesis of Compound 13, except that9,9-dimethyl-7-(10-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)anthracen-9-yl)-9H-fluorene-2-carbonitrilewas used instead of4,4,5,5-tetramethyl-2-(10-(naphthalen-1-yl)anthracen-9-yl)-1,3,2-dioxaborolane.The obtained compound was identified by MS/FAB and ¹H NMR.

C₄₄H₂₇N₃O₂: M⁺ 629.21

Synthesis Example 7: Synthesis of Compound 52

3.44 g (yield: 68%) of Compound 52 was synthesized in the same manner asin the Synthesis of Intermediate I-1, except that4-bromobenzene-1,2-dithiol was used instead of 4-bromobenzene-1,2-diol,and in the same manner as in the Synthesis of Compound 13, except that4-(10-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)anthracen-9-yl)benzonitrilewas used instead of4,4,5,5-tetramethyl-2-(10-(naphthalen-1-yl)anthracen-9-yl)-1,3,2-dioxaborolane.The obtained compound was identified by MS/FAB and ¹H NMR.

C₃₅H₁₉N₃S₂: M⁺ 545.10

Synthesis Example 8: Synthesis of Compound 59

4.20 g (yield: 73%) of Compound 59 was synthesized in the same manner asin the Synthesis of Compound 52, except that2,4-diphenyl-6-(3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)-1,3,5-triazinewas used instead of4-(10-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)anthracen-9-yl)benzonitrile.The obtained compound was identified by MS/FAB and ¹H NMR.

C₃₅H₂₁N₅S₂: M⁺ 575.12

The ¹H NMR and MS/FAB results of the compounds synthesized according toSynthesis Examples 1 to 8 are shown in Table 1.

Methods of synthesizing compounds other than the compound shown in Table1 are recognizable by one of ordinary skill in the art by referring tothe synthesis path and source materials described above.

TABLE 1 HR-EIMS Compound ¹H NMR (CDCl₃, 500 MHz) found calc. 13 δ =7.96-7.92 (m, 2H), 7.83-7.75 (m, 5H), 538.15 538.17 7.71-7.69 (m, 2H),7.67-7.64 (m, 1H), 7.55-7.49 (m, 3H), 7.46-7.44 (m, 1H), 7.39-7.30 (m,7H), 6.97-6.95 (m, 1H) 15 δ = 8.81-7.78 (m, 2H), 7.97-7.87 (m, 4H),489.16 489.15 7.76-7.71 (m, 4H), 7.66-7.64 (m, 1H), 7.55-7.49 (m, 2H),7.38-7.34 (m, 2H), 7.32-7.29 (m, 4H) 16 δ = 7.96-7.94 (m, 2H), 7.86-7.80(m, 4H), 513.13 513.15 7.75-7.72 (m, 2H), 7.69-7.64 (m, 3H), 7.53-7.49(m, 2H), 7.38-7.31 (m, 6H) 20 δ = 8.95-8.92 (m, 2H), 8.69-8.66 (m, 2H),642.22 642.21 8.11-8.07 (m, 4H), 7.95-7.93 (m, 2H), 7.89-7.83 (m, 3H),7.70-7.63 (m, 3H), 7.53-7.45 (m, 4H), 7.39-7.31 (m, 6H) 21 δ = 8.87-8.83(m, 4H), 8.28-8.26 (m, 2H), 643.19 643.20 7.95-7.93 (m, 2H), 7.88-7.85(m, 2H), 7.66-7.60 (m, 5H), 7.58-7.56 (m, 2H), 7.53-7.50 (m, 4H),7.41-7.33 (m, 4H) 27 δ = 8.01-7.92 (m, 5H), 7.81-7.79 (m, 2H), 629.22629.21 7.69-7.64 (m, 4H), 7.53-7.49 (m, 3H), 7.46-7.44 (m, 1H),7.39-7.31 (m, 6H), 1.64 (s, 6H) 52 δ = 8.09-8.07 (m, 1H), 7.92-7.79 (m,6H), 545.09 545.10 7.77-7.67 (m, 4H), 7.60-7.57 (m, 4H), 7.37-7.29 (m,4H) 59 δ = 8.81-8.78 (m, 4H), 8.58-8.53 (m, 2H), 575.13 575.12 8.02-8.00(m, 1H), 7.83-7.75 (m, 5H), 7.62-7.51 (m, 7H), 7.41-7.39 (m, 2H)

Example 1

An anode was prepared by cutting a Corning 15 Ω/cm² (1.200 Å) ITO glasssubstrate to a size of 50 mm×50 mm×0.7 mm, sonicating the glasssubstrate by using isopropyl alcohol and pure water for 5 minutes each,and then irradiating UV light for 30 minutes to ozone to clean the glasssubstrate. Then, the anode was loaded onto a vacuum depositionapparatus.

Then, 2-TNATA, which is a material for forming a hole injection layer,was vacuum-deposited on the substrate to form a hole injection layerhaving a thickness of 600 Å, and then,4,4′-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (hereinafter, referred toas NPB), which is a known hole transporting compound, wasvacuum-deposited on the hole injection layer to form a hole transportlayer having a thickness of 300 Å. 9,10-di-naphthalene-2-yl-anthracene(hereinafter, referred to as ADN), which is a blue fluorescent host, and4,4′-bis[2-(4-(N,N-diphenylamino)phenyl)vinyl]biphenyl (hereinafter,referred to as DPAVBi), which is a blue fluorescent dopant, wereco-deposited on the hole transport layer at a weight ratio of 98:2 toform an emission layer having a thickness of 300 Å.

Then, Compound 13 synthesized according to the embodiments of thepresent disclosure was deposited on the emission layer to form anelectron transport layer having a thickness of 300 Å, and then, LiF,which is a halogenated alkali metal, was deposited on the electrontransport layer to form an electron injection layer having a thicknessof 10 Å, and Al was vacuum-deposited thereon to a thickness of 3,000 Å(i.e., a cathode electrode), thereby forming an LiF/Al electrode andcompleting the manufacture of an organic light-emitting device.

Examples 2 to 8 and Comparative Examples 1 and 3

Organic light-emitting devices were manufactured in the same manner asin Example 1, except that in forming an electron transport layer,compounds shown in Table 2 were used instead of Compound 1.

TABLE 2 Half Driving Current lifespan voltage density BrightnessEfficiency Emission (hr @ Material (V) (mA/cm²) (cd/m²) (cd/A) color 100mA/cm²) Example 1 Compound 13 4.65 50 3,625 7.23 Blue 361 Example 2Compound 15 4.61 50 3,845 7.69 Blue 378 Example 3 Compound 16 4.53 503,625 7.25 Blue 352 Example 4 Compound 20 4.49 50 3,945 7.89 Blue 368Example 5 Compound 21 4.45 50 3,615 7.23 Blue 370 Example 6 Compound 274.70 50 3,525 7.05 Blue 421 Example 7 Compound 52 5.00 50 3,375 6.75Blue 341 Example 8 Compound 59 4.95 50 3,375 6.75 Blue 352 ComparativeCompound 200 5.06 50 3,010 6.52 Blue 325 Example 1 Comparative CompoundA 5.12 50 3,165 6.33 Blue 307 Example 7 Comparative Compound B 5.08 503,225 6.45 Blue 331 Example 3

Referring to Table 2, it was confirmed that the organic light-emittingdevices of Examples 1 to 8 had a low driving voltage, high efficiency,high brightness, and long lifespan characteristics, compared to those ofthe organic light-emitting devices of Comparative Examples 1 to 3.

As described above, an organic light-emitting device including aheterocyclic compound may have a low driving voltage, high efficiency,high luminance, and a long lifespan.

Example embodiments have been disclosed herein, and although specificterms are employed, they are used and are to be interpreted in a genericand descriptive sense only and not for purpose of limitation. In someinstances, as would be apparent to one of ordinary skill in the art asof the filing of the present application, features, characteristics,and/or elements described in connection with a particular embodiment maybe used singly or in combination with features, characteristics, and/orelements described in connection with other embodiments unless otherwisespecifically indicated. Accordingly, it will be understood by those ofskill in the art that various changes in form and details may be madewithout departing from the spirit and scope of the present invention asset forth in the following claims.

What is claimed is:
 1. A heterocyclic compound represented by Formula 1:

wherein, in Formula 1, A₁ and A₂ are each independently a C₅-C₆₀carbocyclic group or a C₂-C₆₀ heterocyclic group, X and Y are eachindependently oxygen (O) or sulfur (S), L₁ and L₂ are each independentlyselected from a substituted or unsubstituted C₅-C₆₀ carbocyclic group ora substituted or unsubstituted C₁-C₆₀ heterocyclic group,*—Si(Q₁)(Q₂)-*′, *—N(Q₁)-*′, *—B(Q₁)-*′, *—C(═O)—*′, *—S(═O)₂—*′, and*—P(═O)(Q₁)-*′, a1 and a2 are each independently an integer selectedfrom 0 to 5, when a1 is 0, *-(L₁)_(a1)-*′ is a single bond, and when a2is 0, *-(L₂)_(a2)-*′ is a single bond, Ar₁ and Ar₂ are eachindependently selected from a substituted or unsubstituted C₃-C₁₀cycloalkyl group, a substituted or unsubstituted C₁-C₁₀ heterocycloalkylgroup, a substituted or unsubstituted C₃-C₁₀ cycloalkenyl group, asubstituted or unsubstituted C₁-C₁₀ heterocycloalkenyl group, asubstituted or unsubstituted C₆-C₆₀ aryl group, a substituted orunsubstituted C₆-C₆₀ aryloxy group, a substituted or unsubstitutedC₆-C₆₀ arylthio group, a substituted or unsubstituted monovalentnon-aromatic condensed polycyclic group, a substituted or unsubstitutedmonovalent non-aromatic condensed heteropolycyclic group,—Si(Q₁)(Q₂)(Q₃), —N(Q₁)(Q₂), —B(Q₁)(Q₂), —C(═O)(Q₁), —S(═O)₂(Q₁), and—P(═O)(Q₁)(Q₂), b1 and b2 are each independently an integer selectedfrom 1 to 5, R₁ and R₂ are each independently selected from hydrogen,deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, asubstituted or unsubstituted C₁-C₆₀ alkyl group, a substituted orunsubstituted C₂-C₆₀ alkenyl group, a substituted or unsubstitutedC₂-C₆₀ alkynyl group, a substituted or unsubstituted C₁-C₆₀ alkoxygroup, a substituted or unsubstituted C₃-C₁₀ cycloalkyl group, asubstituted or unsubstituted C₁-C₁₀ heterocycloalkyl group, asubstituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a substituted orunsubstituted C₁-C₁₀ heterocycloalkenyl group, a substituted orunsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted C₆-C₆₀aryloxy group, a substituted or unsubstituted C₆-C₆₀ arylthio group, asubstituted or unsubstituted C₁-C₆₀ heteroaryl group, a substituted orunsubstituted monovalent non-aromatic condensed polycyclic group, asubstituted or unsubstituted monovalent non-aromatic condensedheteropolycyclic group, —Si(Q₁)(Q₂)(Q₃), —C(═O)(Q₁), —S(═O)₂(Q₁), and—P(═O)(Q₁)(Q₂), c1 and c2 are each independently an integer selectedfrom 1 to 7, m and n are each independently an integer selected from 0to 8, provided that m+n≥1, at least one substituent of the substitutedC₃-C₆₀ carbocyclic group, the substituted C₂-C₆₀ heterocyclic group, thesubstituted C₁-C₆₀ alkyl group, the substituted C₂-C₆₀ alkenyl group,the substituted C₂-C₆₀ alkynyl group, the substituted C₁-C₆₀ alkoxygroup, the substituted C₃-C₁₀ cycloalkyl group, the substituted C₁-C₁₀heterocycloalkyl group, the substituted C₃-C₁₀ cycloalkenyl group, thesubstituted C₁-C₁₀ heterocycloalkenyl group, the substituted C₆-C₆₀ arylgroup, the substituted C₆-C₆₀ aryloxy group, the substituted C₆-C₆₀arylthio group, the substituted C₁-C₆₀ heteroaryl group, the substitutedmonovalent non-aromatic condensed polycyclic group, and the substitutedmonovalent non-aromatic condensed heteropolycyclic group is selectedfrom: deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, anitro group, an amidino group, a hydrazino group, a hydrazono group, asubstituted or unsubstituted C₁-C₆₀ alkyl group, a substituted orunsubstituted C₂-C₆₀ alkenyl group, a substituted or unsubstitutedC₂-C₆₀ alkynyl group, and a substituted or unsubstituted C₁-C₆₀ alkoxygroup; a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynylgroup, and a C₁-C₆₀ alkoxy group, each substituted with at least oneselected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amidino group, a hydrazino group, a hydrazonogroup, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, aC₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,a monovalent non-aromatic condensed heteropolycyclic group,—Si(Q₁₁)(Q₁₂)(Q₁₃), —N(Q₁₁)(Q₁₂), —B(Q₁₁)(Q₁₂), —C(═O)(Q₁₁),—S(═O)₂(Q₁₁), and —P(═O)(Q₁₁)(Q₁₂); a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, and a monovalent non-aromaticcondensed heteropolycyclic group; a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, and a monovalent non-aromaticcondensed heteropolycyclic group, each substituted with at least oneselected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amidino group, a hydrazino group, a hydrazonogroup, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynylgroup, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, —Si(Q₂₁)(Q₂₂)(Q₂₃), —N(Q₂₁)(Q₂₂),—B(Q₂₁)(Q₂₂), —C(═O)(Q₂₁), —S(═O)₂(Q₂₁), and —P(═O)(Q₂₁)(Q₂₂); and—Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁),—S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), Q₁ to Q₃, Q₁₁ to Q₁₃, Q₂₁ to Q₂₃,and Q₃₁ to Q₃₃ are each independently selected from hydrogen, deuterium,—F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, anamidino group, a hydrazino group, a hydrazono group, a C₁-C₆₀ alkylgroup, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxygroup, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, aC₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀aryl group, a C₁-C₆₀ heteroaryl group, a monovalent non-aromaticcondensed polycyclic group, a monovalent non-aromatic condensedheteropolycyclic group, a biphenyl group, and a terphenyl group, and *and *′ each indicate a binding site to a neighboring atom.
 2. Theheterocyclic compound as claimed in claim 1, wherein A₁ and A₂ are eachindependently selected from a benzene group, a naphthalene group, ananthracene group, and a phenanthrene group.
 3. The heterocyclic compoundas claimed in claim 1, wherein X and Y are identical to each other. 4.The heterocyclic compound as claimed in claim 1, wherein L₁ and L₂ areeach independently a divalent group based on a group selected from: abenzene group, a pentalene group, an indene group, a naphthalene group,an azulene group, an indacene group, an acenaphthalene group, a fluorenegroup, a spiro-bifluorene group, a benzofluorene group, adibenzofluorene group, a phenalene group, a phenanthrene group, ananthracene group, a fluoranthene group, a triphenylene group, a pyrenegroup, a chrysene group, a perylene group, a pentacene group, a pyrrolegroup, a thiophene group, a furan group, a silole group, an imidazolegroup, a pyrazole group, a thiazole group, an isothiazole group, anoxazole group, an isoxazole group, a pyridine group, a pyrazine group, apyrimidine group, a pyridazine group, an indole group, an isoindolegroup, an indazole group, a purine group, a quinoline group, anisoquinoline group, a benzoquinoline group, a benzoisoquinoline group, aphthalazine group, a naphthyridine group, a quinoxaline group, aquinazoline group, a cinnoline group, a phenanthridine group, anacridine group, a phenanthroline group, a phenazine group, abenzimidazole group, a benzofuran group, a benzothiophene group, abenzosilole group, a benzothiazole group, an isobenzothiazole group, abenzoxazole group, an isobenzoxazole group, a triazole group, atetrazole group, an oxadiazole group, a triazine group, a carbazolegroup, a dibenzofuran group, a dibenzothiophene group, a dibenzosilolegroup, a benzocarbazole group, a naphthobenzofuran group, anaphthobenzothiophene group, a naphthobenzosilole group, adibenzocarbazole group, a dinaphthofuran group, a dinaphthothiophenegroup, a dinaphthosilole group, a thiadiazol group, an imidazopyridinegroup, an imidazopyrimidine group, an oxazolpyridine group, athiazolpyridine group, a benzonaphthyridine group, an azafluorene group,an azaspiro-bifluorene group, an azacarbazole group, an azadibenzofurangroup, an azadibenzothiophene group, an azadibenzosilole group, anindenopyrrole group, an indolpyrrole group, an indenocarbazole group,and an indolcarbazole group; a benzene group, a pentalene group, anindene group, a naphthalene group, an azulene group, an indacene group,an acenaphthalene group, a fluorene group, a spiro-bifluorene group, abenzofluorene group, a dibenzofluorene group, a phenalene group, aphenanthrene group, an anthracene group, a fluoranthene group, atriphenylene group, a pyrene group, a chrysene group, a perylene group,a pentacene group, a pyrrole group, a thiophene group, a furan group, asilole group, an imidazole group, a pyrazole group, a thiazole group, anisothiazole group, an oxazole group, an isoxazole group, a pyridinegroup, a pyrazine group, a pyrimidine group, a pyridazine group, anindole group, an isoindole group, an indazole group, a purine group, aquinoline group, an isoquinoline group, a benzoquinoline group, abenzoisoquinoline group, a phthalazine group, a naphthyridine group, aquinoxaline group, a quinazoline group, a cinnoline group, aphenanthridine group, an acridine group, a phenanthroline group, aphenazine group, a benzimidazole group, a benzofuran group, abenzothiophene group, a benzosilole group, a benzothiazole group, anisobenzothiazole group, a benzoxazole group, an isobenzoxazole group, atriazole group, a tetrazole group, an oxadiazole group, a triazinegroup, a carbazole group, a dibenzofuran group, a dibenzothiophenegroup, a dibenzosilole group, a benzocarbazole group, anaphthobenzofuran group, a naphthobenzothiophene group, anaphthobenzosilole group, a dibenzocarbazole group, a dinaphthofurangroup, a dinaphthothiophene group, a dinaphthosilole group, a thiadiazolgroup, an imidazopyridine group, an imidazopyrimidine group, anoxazolpyridine group, a thiazolpyridine group, a benzonaphthyridinegroup, an azafluorene group, an azaspiro-bifluorene group, anazacarbazole group, an azadibenzofuran group, an azadibenzothiophenegroup, an azadibenzosilole group, an indenopyrrole group, anindolpyrrole group, an indenocarbazole group, and an indolcarbazolegroup, each substituted with at least one selected from deuterium, —F,—Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidinogroup, a hydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, aC₁-C₂₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₂₀ aryl group, a C₁-C₂₀ heteroarylgroup, a monovalent non-aromatic condensed polycyclic group, amonovalent non-aromatic condensed heteropolycyclic group, a methylphenylgroup, a biphenyl group, and —Si(Q₃₁)(Q₃₂)(Q₃₃); and *—P(═O)(Q₁)-*′, Q₁and Q₃₁ to Q₃₃ are each independently selected from: a C₁-C₁₀ alkylgroup, a C₁-C₁₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, a naphthyl group, a pyridinyl group, a pyrimidinylgroup, a pyrazinyl group, a quinolinyl group, an isoquinolinyl group, aquinoxalinyl group, and a quinazolinyl group; and a phenyl group, abiphenyl group, a terphenyl group, a naphthyl group, a pyridinyl group,a pyrimidinyl group, a pyrazinyl group, a quinolinyl group, anisoquinolinyl group, a quinoxalinyl group, and a quinazolinyl group,each substituted with at least one selected from a C₁-C₁₀ alkyl group, aC₁-C₁₀ alkoxy group, and a phenyl group, and * and *′ each indicate abinding site to a neighboring atom.
 5. The heterocyclic compound asclaimed in claim 1, wherein: at least one of a1 and a2 is nonzero, andL₁ and L₂ are each independently a group represented by Formulae 3-1 to3-47:

wherein, in Formulae 3-1 to 3-47, Y₁ is O, S, C(Z₃)(Z₄), N(Z₅), orSi(Z₆)(Z₇), Z₁ to Z₇ are each independently selected from: hydrogen,deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a cyclopentyl group, a cyclohexylgroup, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group,a phenyl group, a biphenyl group, a terphenyl group, a pentalenyl group,an indenyl group, a naphthyl group, an azulenyl group, an indacenylgroup, an acenaphthyl group, a fluorenyl group, a spiro-bifluorenylgroup, a spiro-benzofluorene-fluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, ananthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a perylenyl group, a pentacenyl group,a pyrrolyl group, a thiophenyl group, a furanyl group, a silolyl group,an imidazolyl group, a pyrazolyl group, a thiazolyl group, anisothiazolyl group, an oxazolyl group, an isoxazolyl group, a pyridinylgroup, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, anindolyl group, an isoindolyl group, an indazolyl group, a purinyl group,a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, anisoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, aquinoxalinyl group, a benzoquinoxalinyl group, a quinazolinyl group, abenzoquinazolinyl group, a cinnolinyl group, a phenanthridinyl group, anacridinyl group, a phenanthrolinyl group, a phenazinyl group, abenzimidazolyl group, a benzofuranyl group, a benzothiophenyl group, abenzosilolyl group, a benzothiazolyl group, an isobenzothiazolyl group,a benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, atetrazolyl group, an oxadiazolyl group, a triazinyl group, a carbazolylgroup, a dibenzofuranyl group, a dibenzothiophenyl group, adibenzosilolyl group, a benzocarbazolyl group, a naphthobenzofuranylgroup, a naphthobenzothiophenyl group, a naphthobenzosilolyl group, adibenzocarbazolyl group, a dinaphthofuranyl group, a dinaphthothiophenylgroup, a dinaphothosilolyl group, a thiadiazolyl group, animidazopyridinyl group, an imidazopyrimidinyl group, an oxazolpyridinylgroup, a thiazolpyridinyl group, a benzonaphthyridinyl group, anazafluorenyl group, an azaspiro-bifluorenyl group, an azacarbazolylgroup, an azadibenzofuranyl group, an azadibenzothiophenyl group, anazadibenzosilolyl group, an indenopyrrolyl group, an indolpyrrolylgroup, an indenocarbazolyl group, and an indolcarbazolyl group, d2 is aninteger selected from 0 to 2, d3 is an integer selected from 0 to 3, d4is an integer selected from 0 to 4, d5 is an integer selected from 0 to5, d6 is an integer selected from 0 to 6, d8 is an integer selected from0 to 8, and * and *′ each indicate a binding site to a neighboring atom.6. The heterocyclic compound as claimed in claim 1, wherein a1 and a2are each independently 0, 1, 2, or
 3. 7. The heterocyclic compound asclaimed in claim 1, wherein Ar₁ and Ar₂ are each independently selectedfrom: a phenyl group, a biphenyl group, a terphenyl group, a naphthylgroup, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenylgroup, a dibenzofluorenyl group, a phenanthrenyl group, an anthracenylgroup, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, achrysenyl group, a perylenyl group, a pentaphenyl group, a hexacenylgroup, a pentacenyl group, a thiophenyl group, a furanyl group, acarbazolyl group, an indolyl group, an isoindolyl group, a benzofuranylgroup, a benzothiophenyl group, a dibenzofuranyl group, adibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolylgroup, a dibenzosilolyl group, a pyridinyl group, an imidazolyl group, apyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolylgroup, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group,a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinylgroup, a quinolinyl group, an isoquinolinyl group, a benzoquinolinylgroup, a phthalazinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a cinnolinyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolylgroup, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group,an imidazopyridinyl group, an imidazopyrimidinyl group, and anazacarbazolyl group; and a phenyl group, a biphenyl group, a terphenylgroup, a naphthyl group, a fluorenyl group, a spiro-bifluorenyl group, abenzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group,an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a perylenyl group, a pentaphenylgroup, a hexacenyl group, a pentacenyl group, a thiophenyl group, afuranyl group, a carbazolyl group, an indolyl group, an isoindolylgroup, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranylgroup, a dibenzothiophenyl group, a benzocarbazolyl group, adibenzocarbazolyl group, a dibenzosilolyl group, a pyridinyl group, animidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolylgroup, an oxazolyl group, an isoxazolyl group, a thiadiazolyl group, anoxadiazolyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a triazinyl group, a quinolinyl group, an isoquinolinyl group, abenzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, aquinoxalinyl group, a quinazolinyl group, a cinnolinyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, aphenazinyl group, a benzimidazolyl group, an isobenzothiazolyl group, abenzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, atetrazolyl group, an imidazopyridinyl group, an imidazopyrimidinylgroup, and an azacarbazolyl group, each substituted with at least oneselected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amidino group, a hydrazino group, a hydrazonogroup, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, abiphenyl group, a terphenyl group, a naphthyl group, a fluorenyl group,a spiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenylgroup, a phenanthrenyl group, an anthracenyl group, a fluoranthenylgroup, a triphenylenyl group, a pyrenyl group, a chrysenyl group, aperylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a thiophenyl group, a furanyl group, a carbazolyl group, anindolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, an imidazolyl group, apyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolylgroup, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group,a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinylgroup, a quinolinyl group, an isoquinolinyl group, a benzoquinolinylgroup, a phthalazinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a cinnolinyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolylgroup, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group,an imidazopyridinyl group, an imidazopyrimidinyl group, an azacarbazolylgroup, and —Si(Q₃₁)(Q₃₂)(Q₃₃); and —Si(Q₁)(Q₂)(Q₃), —C(═O)(Q₁),—S(═O)₂(Q₁), and —P(═O)(Q₁)(Q₂), and Q₁ to Q₃ and Q₃₁ to Q₃₃ are eachindependently selected from: a C₁-C₁₀ alkyl group, a C₁-C₁₀ alkoxygroup, a phenyl group, a biphenyl group, a terphenyl group, a naphthylgroup, a pyridinyl group, a pyrimidinyl group, a pyrazinyl group, aquinolinyl group, an isoquinolinyl group, a quinoxalinyl group, and aquinazolinyl group; and a phenyl group, a biphenyl group, a terphenylgroup, a naphthyl group, a pyridinyl group, a pyrimidinyl group, apyrazinyl group, a quinolinyl group, an isoquinolinyl group, aquinoxalinyl group, and a quinazolinyl group, each substituted with atleast one selected from a C₁-C₁₀ alkyl group, a C₁-C₁₀ alkoxy group, anda phenyl group.
 8. The heterocyclic compound as claimed in claim 1,wherein Ar₁ and Ar₂ are each independently selected from groupsrepresented by Formulae 5-1 to 5-84:

wherein, in Formulae 5-1 to 5-84, Y₃₁ is O, S, C(Z₃₅)(Z₃₆), N(Z₃₇), orSi(Z₃₈)(Z₃₉), Z₃₁ to Z₃₉ are each independently selected from: hydrogen,deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a cyclopentyl group, a cyclohexylgroup, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group,a phenyl group, a biphenyl group, a terphenyl group, a pentalenyl group,an indenyl group, a naphthyl group, an azulenyl group, an indacenylgroup, an acenaphthyl group, a fluorenyl group, a spiro-bifluorenylgroup, a spiro-benzofluorene-fluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, ananthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a perylenyl group, a pentacenyl group,a pyrrolyl group, a thiophenyl group, a furanyl group, a silolyl group,an imidazolyl group, a pyrazolyl group, a thiazolyl group, anisothiazolyl group, an oxazolyl group, an isoxazolyl group, a pyridinylgroup, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, anindolyl group, an isoindolyl group, an indazolyl group, a purinyl group,a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, anisoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, aquinoxalinyl group, a benzoquinoxalinyl group, a quinazolinyl group, abenzoquinazolinyl group, a cinnolinyl group, a phenanthridinyl group, anacridinyl group, a phenanthrolinyl group, a phenazinyl group, abenzimidazolyl group, a benzofuranyl group, a benzothiophenyl group, abenzosilolyl group, a benzothiazolyl group, an isobenzothiazolyl group,a benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, atetrazolyl group, an oxadiazolyl group, a triazinyl group, a carbazolylgroup, a dibenzofuranyl group, a dibenzothiophenyl group, adibenzosilolyl group, a benzocarbazolyl group, a naphthobenzofuranylgroup, a naphthobenzothiophenyl group, a naphthobenzosilolyl group, adibenzocarbazolyl group, a dinaphthofuranyl group, a dinaphthothiophenylgroup, a dinaphothosilolyl group, a thiadiazolyl group, animidazopyridinyl group, an imidazopyrimidinyl group, an oxazolpyridinylgroup, a thiazolpyridinyl group, a benzonaphthyridinyl group, anazafluorenyl group, an azaspiro-bifluorenyl group, an azacarbazolylgroup, an azadibenzofuranyl group, an azadibenzothiophenyl group, anazadibenzosilolyl group, an indenopyrrolyl group, an indolpyrrolylgroup, an indenocarbazolyl group, and an indolcarbazolyl group, e2 is aninteger selected from 0 to 2, e3 is an integer selected from 0 to 3, e4is an integer selected from 0 to 4, e5 is an integer selected from 0 to5, e6 is an integer selected from 0 to 6, e7 is an integer selected from0 to 7, e9 is an integer selected from 0 to 9, and * indicates a bindingsite to a neighboring atom.
 9. The heterocyclic compound as claimed inclaim 1, wherein b1 and b2 are each independently an integer selectedfrom 1 to
 4. 10. The heterocyclic compound as claimed in claim 1,wherein R₁ and R₂ are each independently selected from: hydrogen,deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, and a C₁-C₂₀ alkoxy group; a phenyl group, a biphenylgroup, a terphenyl group, a pentalenyl group, an indenyl group, anaphthyl group, an azulenyl group, a heptalenyl group, an indacenylgroup, an acenaphthyl group, a fluorenyl group, a spiro-bifluorenylgroup, a benzofluorenyl group, a dibenzofluorenyl group, a phenalenylgroup, a phenanthrenyl group, an anthracenyl group, a fluoranthenylgroup, a triphenylenyl group, a pyrenyl group, a chrysenyl group, anaphthacenyl group, a picenyl group, a perylenyl group, a pentaphenylgroup, a hexacenyl group, a pentacenyl group, a rubicenyl group, acoronenyl group, an ovalenyl group, a thiophenyl group, a furanyl group,a carbazolyl group, an indolyl group, an isoindolyl group, abenzofuranyl group, a benzothiophenyl group, a dibenzofuranyl group, adibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolylgroup, a dibenzosilolyl group, and a pyridinyl group; a phenyl group, abiphenyl group, a terphenyl group, a pentalenyl group, an indenyl group,a naphthyl group, an azulenyl group, a heptalenyl group, an indacenylgroup, an acenaphthyl group, a fluorenyl group, a spiro-bifluorenylgroup, a benzofluorenyl group, a dibenzofluorenyl group, a phenalenylgroup, a phenanthrenyl group, an anthracenyl group, a fluoranthenylgroup, a triphenylenyl group, a pyrenyl group, a chrysenyl group, anaphthacenyl group, a picenyl group, a perylenyl group, a pentaphenylgroup, a hexacenyl group, a pentacenyl group, a rubicenyl group, acoronenyl group, an ovalenyl group, a thiophenyl group, a furanyl group,a carbazolyl group, an indolyl group, an isoindolyl group, abenzofuranyl group, a benzothiophenyl group, a dibenzofuranyl group, adibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolylgroup, a dibenzosilolyl group, and a pyridinyl group, each substitutedwith at least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxylgroup, a cyano group, a nitro group, an amidino group, a hydrazinogroup, a hydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, acyclopentyl group, a cyclohexyl group, a cycloheptyl group, acyclopentenyl group, a cyclohexenyl group, a phenyl group, a biphenylgroup, a terphenyl group, a phenyl group substituted with a C₁-C₁₀ alkylgroup, a phenyl group substituted with —F, a pentalenyl group, anindenyl group, a naphthyl group, an azulenyl group, a heptalenyl group,an indacenyl group, an acenaphthyl group, a fluorenyl group, aspiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenylgroup, a phenalenyl group, a phenanthrenyl group, an anthracenyl group,a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, achrysenyl group, a naphthacenyl group, a picenyl group, a perylenylgroup, a pentaphenyl group, a hexacenyl group, a pentacenyl group, arubicenyl group, a coronenyl group, an ovalenyl group, a thiophenylgroup, a furanyl group, a carbazolyl group, an indolyl group, anisoindolyl group, a benzofuranyl group, a benzothiophenyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, a dibenzosilolyl group, a pyridinylgroup, and —Si(Q₃₁)(Q₃₂)(Q₃₃); and —Si(Q₁)(Q₂)(Q₃), and Q₁ to Q₃ and Q₃₁to Q₃₃ are each independently selected from: a C₁-C₁₀ alkyl group, aC₁-C₁₀ alkoxy group, a phenyl group, a biphenyl group, a terphenylgroup, a naphthyl group, a pyridinyl group, a pyrimidinyl group, apyrazinyl group, a quinolinyl group, an isoquinolinyl group, aquinoxalinyl group, and a quinazolinyl group; and a phenyl group, abiphenyl group, a terphenyl group, a naphthyl group, a pyridinyl group,a pyrimidinyl group, a pyrazinyl group, a quinolinyl group, anisoquinolinyl group, a quinoxalinyl group, and a quinazolinyl group,each substituted with at least one selected from a C₁-C₁₀ alkyl group, aC₁-C₁₀ alkoxy group, and a phenyl group.
 11. The heterocyclic compoundas claimed in claim 1, wherein the sum of m and n is 1 or
 2. 12. Theheterocyclic compound as claimed in claim 1, wherein R₁ and R₂ are eachindependently selected from: hydrogen, deuterium, —F, —Cl, —Br, —I, ahydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, and C₁-C₂₀alkoxy group; and a C₁-C₂₀ alkyl group and a C₁-C₂₀ alkoxy group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, and a hydrazono group, and m and n are selected from: mis 0 and n is 1; m is 1 and n is 0; m is 0 and n is 2; m is 1 and n is1; or m is 2 and n is
 0. 13. The heterocyclic compound as claimed inclaim 1, wherein the heterocyclic compound is selected from groupsrepresented by Formulae 1-1 to 1-9:

wherein, in Formulae 1-1 to 1-9, descriptions of X, Y, L₁, L₂, a1, a2,Ar₁, Ar₂, b1, b2, R₁, R₂, c1, c2, m, and n are the same as defined inclaim
 1. 14. The heterocyclic compound as claimed in claim 1, whereinthe heterocyclic compound is represented by Formulae 1-11 to 1-19:

wherein, in Formulae 1-11 to 1-19, descriptions of R₁₁ to R₁₈ are thesame as defined in connection with R₁ and descriptions of R₂₁ to R₂₈ arethe same as defined in connection with R₂, at least one selected fromR₁₁ to R₁₄ is a binding site to the group represented by Formula 2-1, orat least one selected from R₂₁ to R₂₄ is a binding site to the grouprepresented by Formula 2-2, and descriptions of X, Y, L₁, L₂, a1, a2,Ar₁, Ar₂, b1, and b2 are the same as claimed in claim
 1. 15. Theheterocyclic group as claimed in claim 14, wherein Formula 1 isrepresented by Formula 1-11, wherein, in Formula 1-11, (i) R₁₁ to R₁₄are each independently selected from: hydrogen, deuterium, —F, —Cl, —Br,—I, a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, and a C₁-C₂₀alkoxy group; and a C₁-C₂₀ alkyl group and a C₁-C₂₀ alkoxy group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, and a hydrazono group, R₂₁ to R₂₄ are eachindependently selected from: the group represented by Formula 2-2,hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, an amidino group, a hydrazino group, a hydrazono group, aC₁-C₂₀ alkyl group, and a C₁-C₂₀ alkoxy group; and a C₁-C₂₀ alkyl groupand a C₁-C₂₀ alkoxy group each substituted with at least one selectedfrom deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, anitro group, an amidino group, a hydrazino group, and a hydrazono group,and at least one selected from R₂₁ to R₂₄ is the group represented byFormula 2-2, or (ii) R₁₁ to R₁₄ are each independently selected from:the group represented by Formula 2-1, hydrogen, deuterium, —F, —Cl, —Br,—I, a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, and a C₁-C₂₀alkoxy group; and a C₁-C₂₀ alkyl group and a C₁-C₂₀ alkoxy group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, and a hydrazono group, at least one selected from R₁₁to R₁₄ is the group represented by Formula 2-1, and R₂₁ to R₂₄ are eachindependently selected from: hydrogen, deuterium, —F, —Cl, —Br, —I, ahydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, and a C₁-C₂₀alkoxy group; and a C₁-C₂₀ alkyl group and a C₁-C₂₀ alkoxy group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, and a hydrazono group.
 16. The heterocyclic compound asclaimed in claim 14, wherein Formula 1 is represented by Formula 1-11,wherein, in Formula 1-11, R₁₁ to R₁₄ are each independently selectedfrom: hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amidino group, a hydrazino group, a hydrazonogroup, a C₁-C₂₀ alkyl group, and a C₁-C₂₀ alkoxy group; and a C₁-C₂₀alkyl group and a C₁-C₂₀ alkoxy group, each substituted with at leastone selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amidino group, a hydrazino group, and ahydrazono group, R₂₁ and R₂₄ are each independently selected from: thegroup represented by Formula 2-2, hydrogen, deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, and a C₁-C₂₀alkoxy group; and a C₁-C₂₀ alkyl group and a C₁-C₂₀ alkoxy group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, and a hydrazono group, and at least one selected fromR₂₂ and R₂₃ is the group represented by Formula 2-2.
 17. Theheterocyclic compound as claimed in claim 1, wherein the heterocycliccompound is a compound selected from Compounds 1 to 110:


18. An organic light-emitting device comprising: a first electrode; asecond electrode facing the first electrode; and an organic layerbetween the first electrode and the second electrode and comprising anemission layer, wherein the organic layer comprises at least oneheterocyclic compound of claim
 1. 19. The organic light-emitting deviceas claimed in claim 18, wherein the first electrode is an anode, thesecond electrode is a cathode, and the organic layer comprises a holetransport region between the first electrode and the emission layer andan electron transport region between the emission layer and the secondelectrode, wherein the hole transport region comprises a hole injectionlayer, a hole transport layer, an emission auxiliary layer, an electronblocking layer, or a combination thereof, and the electron transportregion comprises a buffer layer, a hole blocking layer, an electroncontrol layer, an electron transport layer, an electron injection layer,or a combination thereof.
 20. The organic light-emitting device asclaimed in claim 18, wherein the organic layer comprises an electrontransport region, wherein the electron transport region comprises the atleast one heterocyclic compound.